Since you have the answers, I'll just show the steps on how to get there.
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Problem 19
[tex](1+4i)^2\\\\(1+4i)(1+4i)\\\\1*1 + 1*4i + 4i*1 + 4i*4i\\\\1 + 4i + 4i + 16i^2\\\\1 + 4i + 4i + 16(-1)\\\\1 + 4i + 4i-16\\\\(1-16) + (4i+4i)\\\\(1-16) + (4+4)i\\\\-15 + 8i\\\\[/tex]
Keep in mind that [tex]i = \sqrt{-1}[/tex] by definition. Squaring both sides leads to [tex]i^2 = -1[/tex]
In the second step, I used the idea that x^2 = x*x. Right after that, I used the FOIL rule to expand everything out.
============================================================
Problem 21
We could follow the same idea as problem 19, but I'll use a different approach.
[tex](A+B)^2 = A^2+2AB+B^2\\\\(3+i)^2 = 3^2 + 2*3*i + i^2\\\\(3+i)^2 = 9 + 6i - 1\\\\(3+i)^2 = 8 + 6i\\\\[/tex]
The formula on the first line is the perfect square binomial formula.
============================================================
Problem 23
The FOIL rule can be used if you want, but I'll use the difference of squares rule instead.
[tex](m+n)(m-n) = m^2 - n^2\\\\(3+5i)(3-5i) = (3)^2 - (5i)^2\\\\(3+5i)(3-5i) = 9 - 25i^2\\\\(3+5i)(3-5i) = 9 - 25(-1)\\\\(3+5i)(3-5i) = 9 + 25\\\\(3+5i)(3-5i) = 34\\\\[/tex]
It turns out that multiplying any complex number of the form a+bi with its conjugate a-bi will result in a purely real number (that has no imaginary part). More specifically: [tex](a+bi)(a-bi) = a^2+b^2[/tex]
============================================================
Problem 25
We could use the difference of squares rule again, but I'll show a different approach. This time using the distribution rule. The FOIL rule could also be used if you wanted.
[tex](6+7i)(6-7i)\\\\x(6-7i)\\\\6x-7xi\\\\6(x)-7i(x)\\\\6(6+7i)-7i(6+7i)\\\\6(6)+6(7i)-7i(6)-7i(7i)\\\\36+42i-42i-49i^2\\\\36-49(-1)\\\\36+49\\\\85\\\\[/tex]
I used x = 6+7i and the substitution property to help distribute. Lines 3 and 6 are where distribution is applied.
Which of the following shows the
Commutative Property?
A 3 + 6 = 6-3
B 3X 6 = 6 = 3
C 3X 6 = 6 - 3 X (3 X 2)
D 3 X 6 = 6 X 3
Answer:
D
Step-by-step explanation:
Commutative switchs the numbers but not with subtraction or divion
Answer:
it is D I know because it is the opposite
Select the correct answer from each drop-down menu.
A machine cuts a strip of carpet into two pleces. The length of the smaller plece is 5 meters greater than 4 the length of the larger piece. If
the length of the smaller piece is 12 meters, the length of the bigger plece is meters and the total length of the carpet is
meters.
Length of larger piece be x
Smaller piece=4x+5x=12m
[tex]\\ \sf\longmapsto 4x+5=4(12)+5=60+5=65m[/tex]
Total length=65+12=77m
The length of the bigger piece is 1.75 meters and the total length of the carpet is 13.75 meters.
Given that length of the smaller piece is 12 meters.
The length of the smaller piece is 5 meters greater than 4 times the length of the larger piece.
Let's represent the length of the larger piece as "x."
Length of the smaller piece = 4 times the length of the larger piece + 5
12 = 4x + 5
Subtracting 5 from both sides:
12 - 5 = 4x
7 = 4x
Dividing both sides by 4:
7/4 = x
1.75 = x
So, the length of the bigger piece is 1.75 meters.
To calculate the total length of the carpet, we add the length of the smaller piece and the length of the bigger piece:
Total length of the carpet = Length of the smaller piece + Length of the bigger piece
Total length of the carpet = 12 + 1.75
Total length of the carpet is approximately 13.75 meters.
Therefore, the length of the bigger piece is 1.75 meters and the total length of the carpet is 13.75 meters.
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On a coordinate plane how are the location of points -6,7 and -6,-7 related
Answer:both involving 6 and 7. (-6,-7) would be in quadrant 3 while point (-6,7) would be on top of it in quadrant 2.
Step-by-step explanation:
The cost of producing key chains with the company logo printed on them consists
of a onetime setup fee of $265.00 plus $0.90 for each key chain produced. This
cost can be calculated using the formula C = 265.00 +0.90p, where p represents
the number of key chains produced and C is the cost. Use the formula to calculate
the cost of producing 2700 key chains.
Answer:
$2695
Step-by-step explanation:
$265 + $0.90p=C
To find out the value of C (cost), we must solve the equation by replacing P (number of keychains) with the given value, 2700.
265 + 0.90(2700) = C
Now, we use order of operations. (PEMDAS)
In this case, the parentheses stand for multiplication. Since multiplication comes first, we multiply 0.90 by 2700.
The product of 0.90(2700) is 2430.
Our new equation should look like this
265 + 2430=C
Adding those together you get 2695, to finish this off, C=$2695
(Side note: be sure to identify what the value is, for example 2695 is the cost of producing 2700 key chains, meaning it's $)
I hope this made sense and helped lol
which option would be correct?
Answer:
similar by angle angle similarity property.
Step-by-step explanation:
they have the right angles, and then the two vertical angles.
:))
Juan exercises more than 30 minutes per day.
Use t to represent Juan's amount of exercise (in minutes per day).
Mr. Walthour is building a storage in a conical shape. The base of the shed is 4 meters in diameter and the height of the shed is 3.8 meters. What is the volume of the shed? Round to the nearest tenth.
I need help , how do we know if the graph are positive or negative
Answer:
The negatives are at the bottom and the positives are at the top, if you need help with the (x,y) let me know!!!
Step-by-step explanation:
Answer:
right and above side of graph are positive
and
left and bottom side of graph are negative
Explain the meaning of 5?
a. 1 + 2 + 3 + 4 + 5
b. 5-4-3-2-1-0
c. 0 x 1 x 2 x 3 x 4 x 5
d. 5 ∙ 4 ∙ 3 ∙ 2 ∙ 1
Teddy has 23 boxes of juice packed and plans to pack 3 additional boxes each hour. Charley has 7 boxes packed and plans to pack 5 additional boxes each hour. The equation below represents when Teddy and Charley will have packed the same number of boxes, based on x number of hours.
23 + 3x = 5x +7
After how many hours will Charley have packed the same number of boxes of juice as teddy?
Answer:
8 hours
Step-by-step explanation:
23 + 3x = 5x + 7
- 3x -3x
23 = 2x + 7
-7 - 7
16 = 2x
16/2 = 2x/2
x = 8
Answer:
BillyBob got it right, well explained..
Step-by-step explanation:
Please Help Me, I don't understand this kind of math
Answer:
x = 9 cm
y = 4 cm
Step-by-step explanation:
The angle markings tell you the three angles of one triangle are equal to the three angles of the other triangle. That means the triangles are "similar", and the lengths of corresponding sides have the same ratio.
The bottom sides, between the angles with 1 mark and 3 marks, are shown as 3 cm in the green triangle and 6 cm in the blue triangle. This tells you all of the the green triangle dimensions are half those of the corresponding dimensions in the blue triangle:
x = (18 cm)/2 = 9 cm
It also tells you the blue triangle dimensions are 2 times those of the green triangle:
y = 2(2 cm) = 4 cm
_____
Additional comments
Corresponding sides having the same ratio means they are proportional (and vice versa). This can be expressed in equation form as ...
y/(2 cm) = (18 cm)/x = (6 cm)/(3 cm)
__
You may want to discuss this problem with your teacher. The side lengths shown in the figure do not form a triangle. The two short sides are too short to connect to the ends of the long side. The figure is impossible.
Natalie and her sister opened a savings account at the same time. Natalie deposited $100 and will deposit $10 each month. Her sister deposited $25 and will deposit $25 each month. When will Natalie have less money in her account that her sister?
Answer:
6 months
Step-by-step explanation:
We can think of Natalie as 100 + 10x and her sister as 25 + 25x. If we put them together, we will get 100 + 10x < 25 + 25x, We can simplify it by moving the 25 to the left side and 10x to the right side. Then we will get 75 < 15x, and the smallest solution is 6 because 5 * 15 is equal to 75
Can someone check my work and show me where I went wrong?
Answer:
the part where it's 25 and 183 should be 5400 if you are rounding to the nearest 10 and then multiplying
Answer:
You made a wrong answer in 183 and 25.
It should be 5,400
Step-by-step explanation:
183 round to the nearest ten = 180
25 round to the nearest ten = 30
180 * 30 = 5,400
Fast help on this!!
Answer:
5 seconds
Step-by-step explanation:
hope it helps
correct me if i'm wrong
A.what is biology
b.what is sciences
Anthony is in a hot air ballon that has taken off and is floating above its launching point. Leroy is standing on the ground, 8 METERS away from the launching point. If Anthony and Leroy are 10 meters apart, how high up is Anthony?
am 7. If the base of the parallelogram is equal to ir and the height is r, then what is the area of the parallelogram?
Step-by-step explanation:
The area of a parallelogram is just base x height, same as a rectangle.
[tex]a=b*h\\a=ir*r[/tex]
If ir is 2 separate variables rather than just 1, that can be simplified to this:
[tex]a=ir^2[/tex]
Team A beat Team B by 15 points in a football game . If a total of 35 points were scored , what was the final score of the game ?
I WILL MARK YOU A BRAINLIEST
Answer:
25-10 (25 - A and 10 - B)
Step-by-step explanation:
25 - 10 equals the 15 point margin
25 plus 10 equals the 35 point score combined
Hope it helps
Will give brainliest!
We know that a + b + c = 7 and [tex]\frac{1}{a+b} + \frac{1}{b+c} +\frac{1}{a+c} =\frac{7}{10}[/tex]. What is the value of [tex]\frac{10a}{b+c} +\frac{10b}{a+c} +\frac{10c}{a+b}[/tex]?
Answer:
19
Step-by-step explanation:
Note that
[tex]\dfrac{10a}{b+c} + \dfrac{10b}{a+c} + \dfrac{10c}{a+b} = 10\left(\dfrac{a}{b+c} + \dfrac{b}{a+c} + \dfrac{c}{a+b} \right)[/tex]
and
[tex]\dfrac{7-b-c}{b+c}+\dfrac{7-a-c}{a+c}+\dfrac{7-a-b}{a+b}=\dfrac{a}{b+c} + \dfrac{b}{a+c} + \dfrac{c}{a+b}[/tex]
from [tex]a+b+c=7 \implies a=7-bc; b = 7-a-c; c = 7-a-b[/tex]
and
[tex]\dfrac{7-b-c}{b+c}+\dfrac{7-a-c}{a+c}+\dfrac{7-a-b}{a+b} = 7\left(\dfrac{1}{a+b}+\dfrac{1}{b+c}+\dfrac{1}{a+c}\right)-3[/tex]
because it is not difficult to note that
[tex]$\sum \dfrac a{b+c}=\dfrac a{b+c}+\dfrac b{c+a}+\dfrac c{a+b}$[/tex]
Therefore,
[tex]7\left(\dfrac{7}{10}\right)-3 = \dfrac{49}{10}-3 =\boxed{ \dfrac{19}{10}} = \dfrac{a}{b+c} + \dfrac{b}{a+c} + \dfrac{c}{a+b}[/tex]
Finally,
[tex]10\left(\dfrac{a}{b+c} + \dfrac{b}{a+c} + \dfrac{c}{a+b} \right) = 10 \cdot \dfrac{19}{10} = 19[/tex]
the probability that a tin of paint is dented is 0.07 out of 3000 tins of paint,how many would you expect to be dented?
Answer:
3000×0.07=210 tins
Step-by-step explanation:
210 tins
Step-by-step explanation:
3000÷100×0.07
=2.1
MARK ME BRAINLIEST PLS!!7. Sid has a board that is 8 5/6
feet long. He cuts a piece off of the board that
is 3 1/4 feet long. How long is the remaining piece of board
Answer:
5 7/12 feet left
Step-by-step explanation:
Step 1: 8 5/6 - 3 1/4
Step 2: = 67/12 (Put into proper fraction)
Step 3: = 5 7/12
Hope that helps :)
Answer:
5 7/12
Step-by-step explanation:
Given that the board is 8 5/6 feet long.
Cuts off 3 1/4 feet.
8 5/6- 3 1/4
Change fractions into improper fractions.
8 5/6=53/6
3 1/4=13/4
-------------------------------------------------------------
53/6x2/2=106/12
13/4x3/3=39/12
106/12-39/12=67/12
=5 7/12
Hope this helps :)
ILL GIVE BRAINIEST IF RIGHT
Is the product of rad 784 and rad 684 rational or irrational? Explain your resonating.
Answer:
Definitely rational because 576 and 684 are both natural numbers
Step-by-step explanation:
Write the prime factorization of 185.
Answer:
5 ⋅ 37
Step-by-step explanation:
185 has factors of 5 and 37.
Answer:
Step-by-step explanation:
All Factors of 185: 1, 5, 37 and 185.
Negative Factors of 185: -1, -5, -37 and -185.
Prime Factors of 185: 5, 37.
Prime Factorization of 185: 5^1× 37^1
Sum of Factors of 185: 228.
Fill in the blank to make each equality true. _ divided by (1/2x^3)=16x^6y^4.
PLS HELP!
Answer:
(8x^9 x y^4) : (1/2x^3)=16x^6y^4
Step-by-step explanation:
8 : 1/2 = 16
x^9 : x^3 = x^6
Equation - [tex]8x^3y^4[/tex] divided by (1/2x^3)=16x^6y^4.
What is equation?In mathematics, an equation is a formula that expresses the equality of two expressions, by connecting them with the equals sign. A mathematical equation is a formula that uses the equals sign to express the equality of two expressions. The meanings of the word equation as well as its cognates in other languages can vary slightly. For instance, in French, an equation is defined as having one or more variables, whereas in English, an equation is any well-formed formula that consists of two expressions linked by the equals sign.
Finding the values of the variables that result in the equality is the first step in solving an equation with variables. The unknown variables are also known as the variables for which the equation must be solved, and the unknown variable values that satisfy the equality are known as the equation's solutions.
Let the required term be z.
[tex]z/ (1/2x^3)=16x^6y^4[/tex]
[tex]z=(16x^6y^4) }{(1/2x^3)}[/tex]
[tex]z = 8x^3y^4[/tex]
Hence, [tex]8x^3y^4[/tex]
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Find the equation of the line with slope m = 2 that contains the point (8,19).
Answer:
y = 2x + 1
Step-by-step explanation:
Pls mark as brainliest
The equation of a line is given by:
y = mx + c
where m is the slope of the line and c is the y-intercept.
The equation of the line with slope m = 2 and point (8, 19) is
y = 2x + 3
What is an equation of a line?The equation of a line is given by:
y = mx + c
where m is the slope of the line and c is the y-intercept.
Example:
The slope of the line y = 2x + 3 is 2.
The slope of a line that passes through (1, 2) and (2, 3) is 1.
We have,
Slope:
m = 2
Point = (8, 19) = (x, y) _____(A)
Now,
The equation of a line is given as,
y = mx + c ______(B)
Substitute (A) into (B)
From (A) we get,
19 = 2 x 8 + c
19 = 16 + c
c = 19 - 16
c = 3
Now,
The equation of the line with slope m = 2 and point (8, 19) is
y = 2x + 3
Thus,
The equation of the line with slope m = 2 and point (8, 19) is
y = 2x + 3
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A taxi service charges $1.00 for the first 1/10 of a mile and $0.10 for each additional 1/10 of a mile after that. fill in the table.
distance traveled
(miles)
9/10
2
3 1/10
10
price
?
(dollars)
Is this a proportional relationship?
Type yes or no
9414 1404 393
Answer:
$1.80, 2.90, 4.00, 10.90
not proportional
Step-by-step explanation:
For some distance d, we have a charge f(d) that is ...
[tex]f(d)=\begin{cases}1.00&0\le d\le0.1\\1.00+0.10\cdot\dfrac{(d-0.1)}{0.10}&0.1<d\end{cases}[/tex]
for d > 0.1, this simplifies to d +0.9.
Then the charges are ...
[tex]\begin{array}{cc}\underline{\text{miles}}&\underline{\text{charge}}\\9/10&1.80\\2&2.90\\3\ 1/10&4.00\\10&10.90\end{array}[/tex]
The different relation for the first 1/10 mile indicates ...
the relationship is not proportional.
The position of an object at any time t is given by
s(t)=3t4−40t3+126t2−9
.
1 Determine the velocity of the object at any time t.
2 Does the object ever stop changing?
3 when is the object moving to the right and when is the object moving to the left
Answer:
Step-by-step explanation:
I will ASSUME that your equation is
s(t) = 3t⁴ - 40t³ + 126t² - 9
1) velocity is the derivative of position
v(t) = s'(t) = 12t³ - 120t² + 252t
2) changing what? position? velocity? acceleration? gender? color?
position No the plot is continuous
velocity Yes both magnitude and direction. Zeros at t = 0, 3, and 7 s
acceleration Yes, both magnitude and direction. Zeros at approx. t = 1.306 and 5.361 s
gender? who knows
color? probably.
3) velocity is positive (moving to the right on a standard number line) for
0 < t < 3 and t > 7
Moves to the left for
t < 0 and 3 < t < 7
1. the velocity of the object at any time "t" is v(t) = 12t³ - 120t² + 252t.
2. the object stops changing at t = 6 and t = 3.5.
3. the object is moving to the right in the interval 0 < t < 3.5 and moving to the left in the interval t > 6.
To determine the velocity of the object at any time "t," we need to find the derivative of the position function "s(t)" with respect to "t."
1. Velocity of the object at any time "t":
The velocity is the rate of change of position with respect to time, which is given by the derivative of the position function, s(t).
s(t) = 3t⁴ - 40t³ + 126t² - 9
To find the velocity function, we take the derivative of s(t) with respect to t:
v(t) = d/dt (3t⁴ - 40t³ + 126t²- 9)
v(t) = 12t³ - 120t² + 252t
So, the velocity of the object at any time "t" is v(t) = 12t³ - 120t² + 252t.
2. Does the object ever stop changing?
The object stops changing when its velocity becomes zero. To find when the velocity is zero, we need to solve the equation v(t) = 0.
12t³ - 120t² + 252t = 0
Now, we can factor out common terms:
t(12t² - 120t + 252) = 0
Now, set each factor equal to zero and solve for "t":
1st factor: t = 0
2nd factor: 12t² - 120t + 252 = 0
To solve the quadratic equation, we can either factor it further or use the quadratic formula. Factoring the quadratic equation gives us:
(t - 6)(12t - 42) = 0
Setting each factor to zero:
1. t - 6 = 0
t = 6
2. 12t - 42 = 0
12t = 42
t = 3.5
So, the object stops changing at t = 6 and t = 3.5.
3. When is the object moving to the right and when is the object moving to the left?
The object is moving to the right when its velocity (v(t)) is positive, and it is moving to the left when its velocity (v(t)) is negative.
Let's analyze the velocity function
v(t) = 12t³ - 120t² + 252t
To find the intervals where the object is moving to the right or left, we need to determine when v(t) is positive or negative.
1. Find critical points by setting v(t) = 0 and solving for "t":
12t³ - 120t² + 252t = 0
As we already found earlier, the critical points are t = 6 and t = 3.5.
2. Test each interval created by these critical points using test points to determine the sign of v(t) in those intervals.
Pick a value of "t" in each of these intervals:
- When t < 3.5 (e.g., t = 0),
- When 3.5 < t < 6 (e.g., t = 4),
- When t > 6 (e.g., t = 7).
Now, substitute these test values into the velocity function v(t):
- v(0) = 12(0)³ - 120(0)² + 252(0) = 0
- v(4) = 12(4)³ - 120(4)² + 252(4) = 192
- v(7) = 12(7)³ - 120(7)² + 252(7) = -588
Based on the test points, we can conclude:
- The object is moving to the right when 0 < t < 3.5 (positive velocity).
- The object is moving to the left when t > 6 (negative velocity).
Therefore, the object is moving to the right in the interval 0 < t < 3.5 and moving to the left in the interval t > 6.
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A coordinate plane with a straight line with a positive slope passing through the points, (0, negative 3) and (3, 4). Choose the answer to complete each statement. The slope of the line is . The y-intercept is at . The graph represents the function
[tex](\stackrel{x_1}{0}~,~\stackrel{y_1}{-3})\qquad (\stackrel{x_2}{3}~,~\stackrel{y_2}{4}) ~\hfill \stackrel{slope}{m}\implies \cfrac{\stackrel{rise} {\stackrel{y_2}{4}-\stackrel{y1}{(-3)}}}{\underset{run} {\underset{x_2}{3}-\underset{x_1}{0}}}\implies \cfrac{4+3}{3}\implies \cfrac{7}{3} \\\\\\ \begin{array}{|c|ll} \cline{1-1} \textit{point-slope form}\\ \cline{1-1} \\ y-y_1=m(x-x_1) \\\\ \cline{1-1} \end{array}\implies y-\stackrel{y_1}{(-3)}=\stackrel{m}{\cfrac{7}{3}}(x-\stackrel{x_1}{0})[/tex]
we can always find the y-intercept by simply setting x = 0, or namely
[tex]y-(-3)=\cfrac{7}{3}(0-0)\implies y+3=\cfrac{7}{3}(0)\implies y+3=0\implies y=-3 \\\\[-0.35em] ~\dotfill\\\\ ~\hfill \stackrel{\textit{y-intercept at}}{(0~~,~-3)}~\hfill[/tex]
Answer:
first one is 7/3
second one is -3
third one is g(x) = 7/3x-3
Step-by-step explanation:
I got it right
on a photograph an ant is enlarged at scale 25:1 In the photo the ant leg is 15 cm what is the actual length of the ants leg
Answer:
0.6 cm
Step-by-step explanation:
15/25=0.6
Answer:
0.6 Is the answer
Step-by-step explanation:
Hope this helped ¬∪ω∪¬
Which choice is equivalent to the expression below?
5 SQR7-4x SQR7-xSQR7
A. 0
B.-2xSQR7
C.-X^2
D. 5 SQR 7 -5xSQR7
I think is the B, tell me if it's correct OK i'm trying to help
Answer:
5√7-5x√7
Step-by-step explanation: