Answer:
20
Step-by-step explanation:
She will be 10 in 5 years witch means she is 5
Double five you get 10
10 + 10 = 20
Answer:
the answer is B.) 20 years old
Step-by-step explanation:
if in 5 years melissa is 10, then right now she is 5 years old. since laura is twice as old as melissa, then laura is currently 10 years old. and if Kim is 10 years older then laura, then Kim is 20 years old
Tl;Dr:
10-5=5
5x2=10
10+10=20
find the distance of the line segment joining the two points (-4 /2 - /12) and (/32, 2/3)
Answer: [tex]4\sqrt{3}[/tex] .
Step-by-step explanation:
Distance formula : Distance between points (a,b) and (c,d) is given by :-
[tex]D=\sqrt{(d-b)^2+(b-a)^2}[/tex]
Distance between points [tex](-4\sqrt{2},\sqrt{12}) \text{ and }(-\sqrt{32}, 2\sqrt{3})[/tex].
[tex]D=\sqrt{(2\sqrt{3}-(-\sqrt{12}))^2+(-\sqrt{32}-(-4\sqrt{2}))}\\\\=\sqrt{(2\sqrt{3}+\sqrt{2\times2\times3})^2+(-\sqrt{4\times4\times2}+4\sqrt{2})^2}\\\\=\sqrt{(2\sqrt{3}-\sqrt{2^2\times3})^2+(-\sqrt{4^2\times2}+4\sqrt{2})^2}\\\\=\sqrt{(2\sqrt{3}+2\sqrt{3})^2+(-4\sqrt{2}+4\sqrt{2})^2}\\\\=\sqrt{(4\sqrt{3})^2+0}\\\\=4\sqrt{3}\text{ units}[/tex]
Hence, the correct option is [tex]4\sqrt{3}[/tex] .
Solve for y 110 75 100 55
Answer:
y = 100
Step-by-step explanation:
x = 25
x+y + 55 = 180 since it is a straight line
25+y+ 55 = 180
Combine like terms
80+y = 180
Subtract 80 from each side
y = 180-80
y = 100
hey can someone help me!! in need of help!! ASAPPPP
Answer:
D
Step-by-step explanation:
To be a function each value of x must correspond to only one, unique value of y.
In the given ordered pairs
Each x- value corresponds to exactly one y- value
What the answer please answer this question now
Answer:
[tex]m\angle Z\approx22.0\textdegree[/tex]
Step-by-step explanation:
First, note that we have a right triangle. Second, we need to find angle Z, and we are given the sides opposite to angle Z and the hypotenuse. Therefore, we can use sine.
Recall that:
[tex]\sin(\theta)=opp/hyp[/tex]
The opposite side is 3 while the hypotenuse is 8. Plug in the numbers and simplify. Use a calculator:
[tex]\sin(\angle Z)=3/8\\\angle Z=\arcsin(3/8)\\\angle Z\approx 22.0243\textdegree[/tex]
Write as an algebraic expression and simplify if possible:
100% of x
What is the answer?
Answer: simplified algebraic expression : x
Step-by-step explanation:
The given phrase : 100 % of x
We can write 100 as 1 because 100% means complete or entire part.
Also, replace 'of' by '×' (Multiply sign).
So, the given phrase will become
1 × x [Algebraic expression]
= x [Simplified]
hence, the simplified algebraic expression is 'x'.
A party rental company has chairs and tables for rent. The total cost to rent 9 chairs and 7 tables is $91. The total cost to rent 3 chairs and 5 tables is $59. What is the cost to rent each chair and each table? Costtorenteachchair:$ Costtorenteachtable:$
Answer:
cost to rent each chair=$1.75, cost to rent each tabble=$10.75
Step-by-step explanation:
Hello, I can help you with this
Step 1
Define
cost to rent a chair=x
cost to rent a table=y
9x=total cost for rent 9 chair
7y = total cost for rent 7 tables
a)The total cost to rent 9 chairs and 7 tables is $91.
in mathematical terms it is
9x+7y=91....equation 1
b) The total cost to rent 3 chairs and 5 tables is
3x+5y=59.... equation 2
and you have 2 equation and 2 unknown terms
let's solve this
from equation 1 isolate x
[tex]9x+7y=91\\9x=91-7y\\x=\frac{91-7y}{9}\\ \\[/tex]
from equation 2 isolate x
[tex]3x+5y=59\\3x=59-5y\\x=\frac{59-5y}{3}[/tex]
now, x= x, so
[tex]x=\frac{91-7y}{9}\\\\\\x=\frac{59-5y}{3} \ \\\ \frac{91-7y}{9}=\frac{59-5y}{3}\\ 3(91-7y)=9(59-5y)\\273-21y=531-45y\\273-531=-45y+21y\\-258=-24y\\y=\frac{258}{24}\\ y=10.75\\[/tex]
now, we know y, use it to find x
[tex]x=\frac{59-5y}{3}\\x=\frac{59-5(10.75)}{3}\\x=\frac{59-53.75}{3}\\\\x=\frac{5.25}{3}\\ x= 1.75\\[/tex]
Have a nice day
I need someone to answer this immediately please. ... The area of a piece of land is 50cm square. Fi d the value of x, if the length
and breadth are given as (x+2) and (x-3)m respectively
options. A. 3
B. 5
C. 7
D. 8
Answer:
x=8
Step-by-step explanation:
Area is equal to
A = l * w
50 = ( x+2) ( x-3)
FOIL
50 = x^2 -3x+2x -6
Combine like terms
50 = x^2 -x -6
Subtract 50 from each side
0 = x^2 -x -56
Factor
What two numbers multiply to -56 and add to -1
-8*7 = -56
-8+7 = -1
0 = ( x-8) ( x+7)
Using the zero product property
x-8 =0 x+7 =0
x = 8 x=-7
Since the length cannot be negative x cannot be negative
x=8
Answer:
8
Step-by-step explanation:
put the 50 under area and continue with like that
Solve 5c − c + 10 = 34.
Answer: 6
Step-by-step explanation: 1. 5c-c= 4c. The equation would then be 4c+10=34.
2. From there, you subtract 10 from both sides of the equation. By doing this, you have the variable and the nonvariable on separate sides of the equation.
3. After doing that, you should have 4c=24. To get the variable by itself, divide both sides by 4. 4c/4 is c and 24/4 is 6.
The final answer is 6. Hope this helped you:)
n the diagram below, points $A,$ $E,$ and $F$ lie on the same line. If $ABCDE$ is a regular pentagon, and $\angle EFD=90^\circ$, then how many degrees are in the measure of $\angle FDE$?
[asy]
size(5.5cm);
pair cis(real magni, real argu) { return (magni*cos(argu*pi/180),magni*sin(argu*pi/180)); }
pair a=cis(1,144); pair b=cis(1,72); pair c=cis(1,0); pair d=cis(1,288); pair e=cis(1,216);
pair f=e-(0,2*sin(pi/5)*sin(pi/10));
dot(a); dot(b); dot(c); dot(d); dot(e); dot(f);
label("$A$",a,WNW);
label("$B$",b,ENE);
label("$C$",c,E);
label("$D$",d,ESE);
label("$E$",e,W);
label("$F$",f,WSW);
draw(d--f--a--b--c--d--e);
draw(f+(0,0.1)--f+(0.1,0.1)--f+(0.1,0));
[/asy]
Answer:
18
Step-by-step explanation:
Each interior angle of a regular pentagon is 108 degrees. So Angle AED is 108 degrees. Since Angle AEF is a straight line (180 degrees), Angle FED is 72. This is because 180-108 = 72. Now, since a triangle has a total of 180 degrees, we add 72 and 90, because those are the 2 degrees we have calculated. This gives us a total of 162. Now, we subtract 162 from 180 to find out the degree of Angle FDE. This is 18. So our final answer is 18.
Sidenote: I hope this answer helps!
The properties of a pentagon and the given right triangle formed by
segments EF and FD give the measure of ∠FDE.
Response:
∠FDE = 18°Which properties of a pentagon can be used to find ∠FDE?The given parameters are;
A, E, F are points on the same line.
ABCDE is a regular pentagon
∠EFD = 90°
Required:
The measure of ∠FDE
Solution:
The points A and E are adjacent points in the pentagon, ABCDE
Therefore;
line AEF is an extension of line side AE to F
Which gives;
∠DEF is an exterior angle of the regular pentagon = [tex]\frac{360 ^{\circ}}{5}[/tex] = 72°∠EFD = 90°, therefore, ΔEFD is a right triangle, from which we have;
The sum of the acute angles of a right triangle = 90°
Therefore;
∠DEF + ∠FDE = 90°
Which gives;
72° + ∠FDE = 90°
∠FDE = 90° - 72° = 18°
∠FDE = 18°
Learn more about the properties of a pentagon here:
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Match each correlation coefficient, r, to its description.
weak negative
correlation
weak positive
correlation
strong positive
correlation
strong negative
correlation
r = −0.83
arrowRight
r = −0.08
arrowRight
r = 0.96
arrowRight
r = 0.06
arrowRight
Answer:
r = -0.83
strong negative correlation
r = -0.08
weak negative correlation
r = 0.96
strong positive correlation
r = 0.06
weak positive correlation
Step-by-step explanation:
In this question, what we are expected to do is to match the values of the correlation given with the type of correlation in which the values are.
When we talk of correlation, we are simply referring to the extent of agreement between the values in the data field.
Correlation has a value between -1 and +1, meaning it could be negative or positive.
Values closer to the extremes i.e (-1 or +1) indicates strong correlation while values farther away, i.e closer to zero indicates a weak relationship.
Let’s answer the questions specifically now:
r = -0.83
This is closer to -1 and it indicates a strong negative correlation
r = -0.08
This indicates a weak negative correlation as it is closer to zero and farther away form -1
r = 0.96
This indicates a strong positive correlation
r = 0.06
This indicates a weak positive correlation
Lines AB and CD are parallel. If ∠3 measures (3x + 20)°, and ∠4 measures 70°, which equation could be used to solve for x
Answer:
(3x + 20)° + 70° = 180°
Step-by-step explanation:
What is the surface area of the regular pyramid? What is the surface area of a square pyramid with a height of 10.4 m and a base side length of 12.4 m? a. 141.4 cm c. 167.4 m b. 162.4 cm d. 188.4 cm
Answer:
A. 141.4 cm
Step-by-step explanation:
The piramide is 141.4cm
The value of the z-scores in a hypothesis test is influenced by a variety of factors. Assuming that all other variables are held constant, explain how the value of z is influenced by each of the following: (Hint: When coming up with your answer, consider how changing the corresponding value in the z formula would change things if its value was increased by 10, 100, 1000, etc. while all other values constant.)
Increasing the difference between the sample mean and the original population mean will result in a(n) (increase/decrease) ______ in the absolute value of z, and a(n) (increase/decrease) ______ in the probability of obtaining a sample with that mean.
Increasing the population standard deviation will result in a(n) (increase/decrease) _____in the absolute value of z, and a(n) (increase/decrease) ______in the probability of obtaining a sample with that mean.
Increasing the number of scores in the sample will result in a(n) (increase/decrease) _____ in the absolute value of z, and a(n) (increase/decrease)______in the probability of obtaining a sample with that mean.
Answer:
Explained below.
Step-by-step explanation:
The z-test statistic is given as follows:
[tex]Z=\frac{\bar X-\mu}{\sigma/\sqrt{n}}[/tex]
Here,
[tex]\bar X=\text{Sample Mean}\\\\\mu=\text{Population Mean}\\\\\sigma=\text{Population standard deviation}\\\\n=\text{Sample size}[/tex]
The p-value is well-defined as per the probability, [under the null-hypothesis (H₀)], of attaining a result equivalent to or greater than what was the truly observed value of the test statistic.
(i)
The difference between the sample mean and the original population mean are directly proportional to the z-test statistic.
So, increasing the difference between [tex]\bar X[/tex] and [tex]\mu[/tex] will lead to an increase in the z-score.
And as the Z-score increases the p-value of the test decreases.
Thus, the complete statement is:
"Increasing the difference between the sample mean and the original population mean will result in an increase in the absolute value of z, and a decrease in the probability of obtaining a sample with that mean."
(ii)
The population standard deviation is inversely proportional to the z-test statistic.
So, increasing the population standard deviation will lead to a decrease in the z-score.
And as the Z-score decreases the p-value of the test increases.
Thus, the complete statement is:
"Increasing the population standard deviation will result in a decrease in the absolute value of z, and an increase in the probability of obtaining a sample with that mean"
(iii)
The number of scores in the sample is directly proportional to the z-test statistic.
So, increasing the number of scores in the sample will lead to an increase in the z-score.
And as the Z-score increases the p-value of the test decreases.
Thus, the complete statement is:
"Increasing the number of scores in the sample will result in an increase in the absolute value of z, and an decrease in the probability of obtaining a sample with that mean."
A diabetes drug cost $78 online. This cost is 75% of the cost of the
prescription in the store. How much is the prescription in the store?
plss help
Answer:
$104
Step-by-step explanation:
If the cost in the store is x we can write:
75%x = 78
0.75x = 78
x = 78 / 0.75 = 104
Answer:
$104 in the store
Step-by-step explanation:
To find the original cost before the discount, you divide the discounted price by the percentage, getting 104.
Suppose an apple picker in China earns an average wage of 45 cents per hour. An apple picker can harvest about 2.0 bushels of apples each hour. One gallon of apple juice requires 40 apples. Each bushel contains about 126 apples. What is the labor cost of one gallon of apple juice in dollars?
Answer:
0.0398 dollars
Step-by-step explanation:
We are told in the question that
An apple picker in China earns an average wage of 45 cents per hour.
Mathematically
1 hour= 45 cents............ Equation 1
An apple picker can harvest about 2.0 bushels of apples each hour.
Mathematically
2.0 bushels = 1 hour ..............Equation 2
We are told that each bushel contains about 126 apples
1 bushel = 126 apples
2 bushels =
126 × 2
= 252 apples
Combining Equation 1 and 2 together,
We can say
An apple picker in 1 hour harvests 2 bushels of apples which is 252 apples and is paid 45 cents
1 hour = 2 bushels of apples
1 hour = 252 apples
1 hour = 45 cents
Hence we can say fro harvesting 252 apples, an apples picker is paid 45 cents
Mathematically,
252 apples = 45 cents
One gallon of apple juice requires 40 apples
We are to calculate the labor cost of one gallon of apple juice in dollars
If : 252 apples = 45 cents
40 apples = X cents
Cross Multiply
40 × 25 = 252 × X
X = (40× 25) ÷ 252
X = 3.984063745 cents
Hence the labor cost of 40 apples = 3.984063745 cents
Approximately = 3.98 cents
Converting 3.98 cents to dollars
100 cents = 1 dollar
3.98 cents =
= 3.98/100
= 0.0398 dollars.
Therefore, the labor cost of one gallon of apple juice in dollars is 0.0398 dollars.
In the given graph of a cubic polynomial, what are the number of real zeros and complex zeros, respectively?
Answer: 1 real and 2 complex.
Step-by-step explanation:
A cubic polynomial is written as:
a*x^3 + b*x^2 + c*x + d
And the zeros are such that:
a*x^3 + b*x^2 + c*x + d = 0
As the degree of the polynomial is 3, then we have 3 solutions (where some of them may be equal)
Now, an easy way to see the real and complex zeros of a polynomial is:
If after a change in curvature, the line touches the x-axis : that is a real zero
if it does not, then there we have a complex zero.
Here we can see two lines that do not touch the x-axis and one line that does touch the x-axis.
Then we have 2 complex zeros and one real zero.
Identify which of these designs is most appropriate for the given experiment: completely randomized design, randomized blockdesign, or matched pairs design.
A drug is designed to treat insomnia. In a clinical trial of the drug, amounts of sleep each night are measured before and after subjects have been treated with the drug.
The most appropriate is (randomized block, matched pairs, completly randomized) design.
Answer:
Matched pairs design
Step-by-step explanation:
Looking at the options;
-It's not a completely randomized design because a randomized design will assign all individuals to a group which in this case it doesn't.
- It's not a randomized block design because randomized block design will group the subjects in question into 2 or more blocks which have a common characteristic and will then randomly assign subjects in each of the blocks.
-It's a matched pair because every individual/subject undergoes measurements both before and after being treated with the drugs.
Thus, the correct option is matched pairs design.
how do you know if the solutions to a quadratic equations are inside, outside, on, inside and on, or outside and on the parabola? with the different equality signs?
Answer:
Option (1)
Step-by-step explanation:
Given quadratic equation in this question is,
y < -x²+ 4x + 5
Now we will convert this standard quadratic equation into vertex form,
y < -(x² - 4x) + 5
y < -[x² - 2(2)x + 2²] + 5
y < -(x - 2)²+ 5
This equation is in the form of y < a(x - h)² + k
where (h, k) is the vertex of the parabola.
Therefore, y < -(x - 2)²+ 5 will show the parabola with properties as,
1). Parabola having vertex at (2, 5).
2). Coefficient 'a' is negative, so parabola will open downwards.
3). In the inequality notation of less than, (sign < ) will show the solution area inside the parabola.
[If an inequality has a sign of greater than, solution area will be outside the parabola.]
Therefore, Option (1) will be the answer.
Which store will give Martina the best deal if she has 60 people in attendance?
Igloo
Tasty
Fred’s
Answer:
Fred's
Step-by-step explanation:
Igloo 1.75(60) + 75 = 180
Tasty 2(60) + 80 = 200
Fred's 1.25(60) + 90 = 151.25
Answer: fred's
Step-by-step explanation:
Please answer this in two minutes
Answer: 9.9
Step-by-step explanation:
SINE RULE:
7/sin(31) = q / sin(47)
Therefore q = 7 / sin(31) * sin(47)
which equals: 9.9 to the nearest tenth.
Answer:
q = 9.9
Step-by-step explanation:
We can use the rule of sines
sin R sin Q
------------- = ------------
PQ PR
sin 31 sin 47
------------- = ------------
7 q
Using cross products
q sin 31 = 7 sin 47
Divide by sin 31
q = 7 sin 47 / sin 31
q =9.939995043
To the nearest tenth
q = 9.9
Write the equation of a circle with center (7, -12) and radius 9.
Answer:
( x-7)^2 + ( y+12) ^2 = 81
Step-by-step explanation:
The equation of a circle can be written in the form
( x-h)^2 + ( y-k) ^2 = r^2 where ( h,k) is the center and r is the radius
( x-7)^2 + ( y--12) ^2 = 9^2
( x-7)^2 + ( y+12) ^2 = 81
Answer:
(x - 7)² + (y + 12)² = 81
Step-by-step explanation:
The equation of a circle in standard form is
(x - h)² + (y - k)² = r²
where (h, k) are the coordinates of the centre and r the radius
Here (h, k) = (7, - 12) and r = 9, thus
(x - 7)² + (y - (- 12))² = 9², that is
(x - 7)² + (y + 12)²= 81
simultaneous equations 2x + y = 21 x - y = 6
Step-by-step explanation:
this is substitution method
Answer:
2x + y = 21
+
x - y = 6
_________
3x = 27
x = 27 ÷ 3
x= 9
x - y = 6
9 - y = 6
9 - 6 = y
3 = y
Therefore, x= 9 and y = 3
Which of the following shows the division problem below in synthetic division form?
Answer: D
Step-by-step explanation:
In synthetic division, if the divisor is an expression like x+3, you should always switch it to if x+3 were equal to 0.
[tex]x+3=0\\x=-3[/tex]
So, you should use -3. The only options with -3 are B and D.
The coefficients for the dividend are 7, -2, and 4, so D is the correct answer.
Hope this helps! If you still have questions, please ask.
Find the Equation of the Parallel Line
of
Instructions: Find the equation of the line through point (-1, 4) and parallel to
5x +y = 4. Use a forward slash (i.e. "/") for fractions (e.g. 1/2 for ).
y =
Answer:
y = -5x - 1
Step-by-step explanation:
Let the equation of a line parallel to the given line is,
y - y' = m(x - x')
Where m = slope of the line
And line passes through (x', y')
Equation of a line has been given as,
5x + y = 4
y = -5x + 4
Slope of this line = -5
By the property of parallel lines "slope of the parallel lines are same",
m = -5
Parallel line passing through (-1, 4) and slope 'm' = -5 will be,
y - 4 = -5(x + 1)
y - 4 = -5x - 5
y = -5x - 5 + 4
y = -5x - 1
Therefore, equation of the parallel line will be,
y = -5x - 1
Construct the cumulative frequency distribution for the given data.
Age (years) of Best Actress when award was won Frequency
20-29 27
30-39 37
40-49 11
50-59 3
60-69 5
70-79 1
80-89 2
Age (years) of Best Actress when award was won Cumulative Frequency
Less than 30
Less than 40
Less than 50
Less than 60
Less than 70
Less than 80
Less than 90
Answer:
Age Frequency Cumulative Frequency
Less than 30 27 27
Less than 40 37 27 + 37 = 64
Less than 50 1 1 64 + 11 = 75
Less than 60 3 75 + 2 = 77
Less than 70 5 77 + 5 = 82
Less than 80 1 82 + 1 = 83
Less than 90 2 83 +2 = 85
Step-by-step explanation:
Given:
The Frequency Distribution table of ages of best actresses when award was won
To find:
Construct the cumulative frequency distribution
Solution:
In order to construct cumulative frequency distribution for the given data, each frequency from above table is added to the sum of the previous frequencies. For example, frequency for Less than 40 is 37 and the previous frequency (less than 30) is 27 so in order to calculate cumulative frequency 27 i.e. previous frequency is added to 37 (frequency of less than 30). The complete table is given above.
A 450m long field is drawn to a scale 1cm to 90cm.find the lenth of drawing
Answer:
5 cm
Step-by-step explanation:
The length of the drawing will be 450 / 90 = 5 cm.
which explicit formula can be used to find the number of rabbits in the nth generation ?
Answer:
A. an = 3(6)^(n-1)
Step-by-step explanation:
1st generation: n = 1:
a1 = 3*6^(1-1) = 3*6^0
= 3
n = 2:
a2 = 3*6^2-1
= 3*6
=18
n = 3
a3 = 3*6^(3-1)
= 3*6^2
= 106.
The solution is Option A.
The geometric progression is given by the equation aₙ = 3 ( 6 )ⁿ⁻¹ , where n is the number of terms
What is Geometric Progression?
A geometric progression is a sequence in which each term is derived by multiplying or dividing the preceding term by a fixed number called the common ratio.
The nth term of a GP is aₙ = arⁿ⁻¹
The general form of a GP is a, ar, ar2, ar3 and so on
Sum of first n terms of a GP is Sₙ = a(rⁿ-1) / ( r - 1 )
Given data ,
Let the geometric progression be represented as A
Let the number of terms be represented as n
Now , the first term a₁ = 3 rabbits
The second term a₂ = 3 x 6 = 18 rabbits
The third term a₃ = 18 x 6 = 108 rabbits
So , the common ratio r = second term / first term
Substituting the values in the equation , we get
Common ratio r = 18/6 = 6
Now , the geometric progression A is given by the equation ,
The nth term of a GP is aₙ = arⁿ⁻¹
Substituting the values in the equation , we get
aₙ = 3 ( 6 )ⁿ⁻¹
Therefore , the value of A is aₙ = 3 ( 6 )ⁿ⁻¹
Hence , the equation is aₙ = 3 ( 6 )ⁿ⁻¹
To learn more about geometric progression click :
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Solve for x. 3 1 2 140
Answer:
Hey there!
Angle QRS is 70, and since it is located on the circle, we have a useful formula. If 141x-1 is called y, then 70 is half of that.
Thus, we have 141x-1=140
141x=141
x=1
Hope this helps :)
20
The average annual energy cost for a certain home is
$4,334. The homeowner plans to spend $25,000 to
install a geothermal heating system. The homeowner
estimates that the average annual energy cost will
then be $2,712. Which of the following inequalities
can be solved to find t, the number of years after
installation at which the total amount of energy cost
savings will exceed the installation cost?
A) 25,000 > (4,334 - 2,712)
B) 25,000 < (4,334 - 2,712)
C) 25,000 - 4,334 > 2,712t
D) 25,000 >
4,332
2,712t
Answer:
This is my first question but I think it's c
Step-by-step explanation:
25,000-4334=20,666
20,666/2712=7.62 which rounds to 8
. Factorize a² +3ab - 5ab - 15b²
Answer:
a² +3ab - 5ab - 15b² = (a+3b) (a-5b)
Step-by-step explanation:
We need to factorize a² +3ab - 5ab - 15b². Firstly we need to rearrange the expression such that,
[tex]a^2-5ab+3ab-15b^2=(a^2-5ab)+(3ab-15b^2)[/tex]
Now taking a common from the first two terms and 3b from last two terms, then :
[tex](a^2-5ab)+(3ab-15b^2)=a(a-5b)+3b(a-5b)[/tex]
In the above expression, a factor (a-5b) is in both the terms. It would mean that,
[tex]a(a-5b)+3b(a-5b)=(a+3b)(a-5b)[/tex]
So, the factors of a² +3ab - 5ab - 15b² are (a+3b) (a-5b).