Solve the following system of equations using elimination:
-x+5y=8
And
3x+7y=-2

Answers

Answer 1

Answer:

x=-3, y=1. (-3, 1).

Step-by-step explanation:

-x+5y=8

3x+7y=-2

----------------

3(-x+5y)=3(8)

3x+7y=-2

--------------------

-3x+15y=24

3x+7y=-2

------------------

22y=22

y=22/22

y=1

-x+5(1)=8

-x+5=8

-x=8-5

-x=3

x=-3


Related Questions

how do i graph for this, i struggle

Answers

The equation of line passes through the point (2, 3) will be;

⇒ y = 1/2x + 2

And, Graph of this equation of line is shown in figure.

What is Equation of line?

The equation of line in point-slope form passing through the points

(x₁ , y₁) and (x₂, y₂) with slope m is defined as;

⇒ y - y₁ = m (x - x₁)

Where, m = (y₂ - y₁) / (x₂ - x₁)

Given that;

The point on the line are (2, 3).

And, The perpendicular line is,

⇒ y - 4 = - 2 (x + 3)

⇒ y -  4 = - 2x - 6

⇒ y = - 2x - 2

Now,

Since, The equation of line passes through the point (2, 3).

So, We need to find the slope of the line.

Since, The product of slope of the perpendicular line is - 1.

Hence, Slope of the given perpendicular line is,

⇒ y = - 2x - 2

m = dy/dx = - 2

m = - 2

So, The slope of line is,

⇒ m₂ = - 1/m

         = 1/2

Thus, The equation of line with slope 1/2 is,

⇒ y - 3 = 1/2 (x - 2)

⇒ y - 3 = 1/2 (x - 2)

⇒ y - 3 = 1/2x - 1

⇒ y = 1/2x - 1 + 3

⇒ y = 1/2x + 2

Therefore, The equation of line passes through the point (2, 3) will be;

⇒ y = 1/2x + 2

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A jet accelerates from rest to 300 m/s over a time of 23 seconds. What is its acceleration?

Answers

Answer:

13.04m/s^2

Step-by-step explanation:

v=u+at

therefore

a=v-u÷t

300m/s-0÷23s

=13.04m/s^2

A financial advisor has recommended two possible mutual funds for investment: Fund A and Fund B. The return that will be achieved by each of these depends on whether the economy is good, fair, or poor. A payoff table has been constructed to illustrate this situation:

STATE OF NATURE

INVESTMENT GOOD ECONOMY FAIR ECONOMY POOR ECONOMY

Fund A $10,000 $2,000 –$5,000

Fund B $6,000 $4,000 0

Probability 0. 2 0. 3 0. 5

Draw the decision tree to represent this situation.


Perform the necessary calculations to determine which of the two mutual funds is better. Which one should you choose to maximize the expected value?


Suppose there is a question about the return of Fund A in a good economy. It could be higher or lower than $10,000. What value for this would cause a person to be indifferent between Fund A and Fund B (i. E. , the EMVs would be the same)?

Answers

$21,500  this would be cause a person to be indifferent between Fund A and Fund B (i. E. , the EMVs would be the same)

EMV 1 = 0.2*10,000 + 0.3*2,000 + 0.5*-5,000 = $100EMV 2 = 0.2*6,000 + 0.3*4,000 + 0.5*-0 = $2,400.

Comparing both funds based on EMV calculations, Fund B shows a higher EMV. Therefore, to maximize expected value, we should invest in Fund B with an expected value of $2,400. First, his EMV for Fund A is not the same as Fund A's return being higher or lower in good economic conditions. Therefore, the EMC can also be higher or lower. But obviously the economy changes quickly sometimes. You don't always get the same return. So relying solely on returns is risky. Relying heavily on favorable economic conditions makes Fund A vulnerable to change and increases investor risk, so investors need to be more diversified. We can do the calculation:

Fund A return in good economy = Difference between A and B: EMV (Fund A) = EMV (Fund B) 0.2*X + 0.3(2,000) + 0.5(- 5,000) = 2 4,000.2X = 4,300X = $21,500.

Therefore, if the economy is good, Fund A's return should be $21,500 for there to be indifference between Fund A and the fund B.

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Complete the following function table for the linear equation y=4x-1

Answers

First we can find value of x and. When x=0 then y=-1  and x=1 then y= 3

What is linear equation explain?

A linear equation is an algebraic equation of the form y=mx+b involving only a constant and a first-order (linear) term where m is the slope and b is the y-intercept.So the above given equation is called a "linear equation of two variables," where y and x are the variables.

How do you find the value of Y?

Finding the y value is easy if you know the slope of the line and the x coordinate. Review the equation for the slope of a line. The equation for finding the slope is: m = [y1 - y2] / [x1 - x2]. If you know x, you can solve for y to find the y value for the slope of the line.

Now we have y= 4x-1

lets x=0   then y= -1

     x=1      then y=3

     x=2     then y=7

To find slope

y=mx+c

y= 4x-1

so by comparing we can find m=4

Then we can evaluate given equation y=4x-1

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( 40 POINTS AND BRAINLIEST , HELP ASAP !!!!!!!!! )

Brooke and Daniel are playing a game that involves one flip of a coin and one spin of a spinner with 3 sections. They each drew a tree diagram to represent the sample space of possible outcomes.

Whose tree diagram is correct ?

A. Brooke’s
B. Daniel sure
C. Both Brooke’s and Daniel’s
D. Neither Brooke’s nor Daniel’s

Answers

Answer:

Daniel's is correct

Step-by-step explanation:

Daniel split the coin toss into Heads and Tails and has 3 sections for the spinner coming off of each coin toss branch.

Jessica is wanting to buy a 10.00 box of candy. The sales tax is 5%. How much is the total for the candy?

$15.00
$12.00
$11.00
$10.50

Answers

Answer: To find the total cost of the candy including the sales tax, we first need to calculate the amount of tax by multiplying the cost of the candy by the tax rate.

The cost of the candy is 10.00.

The tax rate is 5%, which can be written as 0.05.

The total cost of the candy would be

10 + (10*0.05) = 10+0.5 = 10.50

So the correct answer is $10.50.

Step-by-step explanation:

Use properties of operations to complete the equivalent expressions. 3(c−4)=​___c−​___ 3(c−4)

Answers

Using properties of operations, the expression is 3(c-4)= 3c-12.

What are the properties of operations?

Properties of additionAddition of whole numbers is both associative and commutative.The identity for adding whole numbers is 0, or zero.Properties of MultiplicationThe identity for multiplying whole numbers is 1.Multiplication of whole numbers is both associative and commutative.Distribution favours multiplication over addition.Properties of Division and subtractionDivision is not associative.Subtraction is not commutative.

Now, we are given the expression 3(c-4)

Using the properties of operation,

3(c-4)= (3*c)-(3*4)

= 3c-12

Hence, the equivalent expressions are 3(c-4)=3c-12.

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Question- Use properties of operations to complete the equivalent expressions. 3(c−4)=​___c−​___

What’s 36/6 as a whole number?

Answers

Answer:

It should be 6 because 6x6 is 36

Answer:

6

Step-by-step explanation:

fractions are division so just divide 36 by 6 and you will get 6 which is your answer

36/6 =

36 : 6 =

6

Individual bottles of water are filled by a machine at a factory with an amount of water that is approximately normal with a mean of 505 mL and a standard deviation of 10 mL. A random sample of 16 bottles is selected for a quality inspection What is the probability that the mean amount of water in these 16 bottles is within 5 mL of the population mean? Choose 1 answer: P(500 < < 510) 0.38 B P(500 < t <510) 0.45 P(500 < & <510) 0.88 P(500 <<510) 0.95 We cannot calculate this probability because the sampling distribution is not normal.

Answers

The probability of the event that the mean amount of water in the 16 bottles is within 5 mL of the population mean is approximately 0.9544, which is closest to 0.95.

The correct answer is: D. P(500 <<510) 0.95.

Here, we have to find the probability that the mean amount of water in the 16 bottles is within 5 mL of the population mean (505 mL), we need to calculate the probability P(500 <x < 510), where x is the sample mean.

Given that the sample size (n) is 16 and the population standard deviation (σ) is 10 mL, we can use the Central Limit Theorem to approximate the sampling distribution of the sample mean.

The Central Limit Theorem states that for a sufficiently large sample size (n ≥ 30), the sampling distribution of the sample mean will be approximately normal, regardless of the shape of the population distribution.

The mean of the sampling distribution of the sample mean is equal to the population mean (μ) and the standard deviation of the sampling distribution (standard error) is given by σ/√n, where σ is the population standard deviation and n is the sample size.

In this case:

μ = 505 mL (population mean)

σ = 10 mL (population standard deviation)

n = 16 (sample size)

The standard error (SE) of the sample mean is:

SE = σ/√n = 10/√16 = 10/4 = 2.5 mL

Now, we need to find the z-scores for 500 mL and 510 mL:

z₁ = (500 - μ) / SE = (500 - 505) / 2.5 = -2

z₂ = (510 - μ) / SE = (510 - 505) / 2.5 = 2

Using the z-table or a statistical calculator, we can find the probabilities corresponding to these z-scores:

P(z < -2) ≈ 0.0228

P(z < 2) ≈ 0.9772

Now, to find the probability that the sample mean is within 5 mL of the population mean (P(500 <x < 510)), we subtract the probability corresponding to the lower z-score from the probability corresponding to the higher z-score:

P(500 < x < 510) ≈ P(z < 2) - P(z < -2) ≈ 0.9772 - 0.0228 ≈ 0.9544

So, the probability of the event that the mean amount of water in the 16 bottles is within 5 mL of the population mean is approximately 0.9544, which is closest to 0.95.

The correct answer is: D. P(500 <<510) 0.95

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If Y=6 and X=10 then find the value of y when x=8​

Answers

Y=85857483993&4 but Y=85 for short

Answer:

when x=10 & y=6

10-6=4 so,

x=8

y=4

Find the value of x.
x 13 39​

Answers

Answer:

13x-39=39

13x=78

 the answer is x=6

PLEASE HELP ME, ILL BRAINLIEST YOU

Answers

X always equals 90 in a rhombus and y is 47

The High Roller in Las Vegas is now the world’s tallest Ferris wheel. The Ferris wheel has 520 ft. diameter, and the top of the Ferris wheel is 550 ft. off the ground. What would the vertical shift (k) be for this Ferris wheel?

Answers

Answer:

30

Step-by-step explanation:

Is 10 24 26 a right triangle?

Answers

Yes, A triangle has sides of lengths 10, 24, and 26 is a right triangle.

A right-angled triangle is a triangle with one of the angles at 90 degrees. A 90-degree angle is called a right angle.

The formula states that in a right triangle:

The square of the hypotenuse is equal to the sum of the square of the base and the square of the altitude.

(Hypotenuse)² = (Base)² + (Altitude)²

c²=a²+b²

The three numbers which satisfy the above formula are the Pythagorean triplets

Properties of right angle:

The largest angle is always 90º and called the hypotenuse which is always the side opposite to the right angle.The measurements of the sides follow the Pythagoras rule, which cannot have any obtuse angle.

consider c=26 a=10, b=24 substitute in above formula:

26²=10²+24²

⇒676=100+576

⇒676=676

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is dilated from the origin to create segment A prime B prime at A' (0, 6) and B' (6, 9). What scale factor was segment AB dilated by

Answers

The scale factor of segment AB was 1.94.

What is scale factor?

Scale factor is a number by which a given set of measurements is multiplied in order to increase or decrease the size of the measurements. It can be used to enlarge or reduce the size of an object, image, or diagram. It is a useful tool in many areas of mathematics, including geometry, engineering, and computer graphics.

The scale factor for segment AB can be found by taking the ratio of the lengths of the two segments. To calculate this, use the distance formula to find the length of segment AB and A'B' and set them equal to each other.

The distance formula is: d = √[(x2-x1)^2 + (y2-y1)^2]

The coordinates of A and B are (0, 0) and (6, 9), respectively. The coordinates of A' and B' are (0, 6) and (6, 9), respectively.

For segment AB, the distance formula becomes: d = √[(6-0)^2 + (9-0)^2], which simplifies to d = √[36 + 81], which simplifies to d = √117.

For segment A'B', the distance formula becomes: d = √[(6-0)^2 + (9-6)^2], which simplifies to d = √[36 + 9], which simplifies to d = √45.

The scale factor is then found by taking the ratio of the two distances, √117/√45, which simplifies to √117/3, or approximately 1.94. Therefore, the scale factor of segment AB was 1.94.

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2 Lauren is using 10 pink beads and 5 black a bracelet. Which beads to decorate ratio compares the number of black beads to the total number of beads She is using?​

Answers

When b does not equal 0, an ordered pair of numbers a and b, represented as a / b, is said to be a ratio.

What is ratio?

A comparison between two items by means of a number. (arithmetic) comparing two quantities' relative magnitudes (usually expressed as a quotient).

When the second number in the ordered pair, b, is not equal to 0, the ratio is expressed as a/b. An equation in which two ratios are made equal is known as a percentage. As an illustration, you could express the ratio as 1: 3 if there is 1 guy and 3 girls (for every one boy there are 3 girls) 40% are girls, and 14% are boys.

Comparing two numbers by dividing them is how ratios work. Your formula would be A/B if you were contrasting one data point (A) with another data point (B). By doing so, you are multiplying information A by information B. Your ratio will be 5/10, for instance, if A is 5 and B is 10.

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Please help quickly thanks

Answers

Answer:

69000

Step-by-step explanation:

math

At the Middleton School festival, a tent covers a rectangular space 30 1/2 yards long and 9 1/3 yards wide. What is the area, in square yards, covered by the tent?

Answers

287.64 square yards

what is the following is a like radical to 3/6x^2?
NO FILES WILL BE REPORTED!!!

Answers

Answer:

I guess is this but Im not sure

To divide 572 4, Stanley estimated to
place the first digit of the quotient. In which
place is the first digit of the quotient?

Answers

Answer:

The hundreds place

Step-by-step explanation:

143, first digit is , 1 is in the hundreds place

i will give brainliest!!

find the radius of a circle if the area is 15 cm squared

Answers

Answer:

2.19

Step-by-step explanation:

Why do we use similarity transformation?

Answers

The goal of using similarity transformations is to make the evaluation of a matrix's eigenvalues less complicated. In fact, the computation of the eigenvalues would be instantaneous if a given matrix could be translated into a similar matrix in diagonal or triangular form.

A geometric similarity or a matrix transformation that produces a likeness are both covered by the term "similarity transformation."

A conformal mapping with a similarity transformation is one whose transformation matrix A' has the formula A'=BAB⁻¹, where A and A' are referred to as similar matrices.

Space-based items are converted to equivalent objects by similarity transformations. Fractals and iterated function systems have a lot to do with similarity transformations and the idea of self-similarity.

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What will be the successor of the greatest 7-digit number and the predecessor of the smallest 8-digit number? Is there any relation between these two numbers? If yes, state the relation.

Answers

Answer:

The largest 7-digit number, is a 7 nine digits, this number is:

9,999,999

If we subtract one, we get a 7-digit number smaller than this one.

if we add one, we get an 8-digit number.

Then this one is the greatest 7-digit number.

The successor of this number, is equal to the number plus one:

9,999,999 + 1 = 10,000,000

The smallest 8-digit number is the first 8-digit number, and we know that this one is:

10,000,000

And the predecessor is equal to this number minus one:

10,000,000 - 1 = 9,999,999

So we can conclude that:

The successor of the greatest 7-digit is the smallest 8-digit number

The predecessor of the smallest 8-digit number is the greatest 7-digit number.

And we could interpolate this for any N-digit number, such that:

The successor of the greatest N-digit is the smallest (N + 1)-digit number

The predecessor of the smallest (N + 1)-digit number is the greatest N-digit number.

Aida, Bernado and Cristiano need $30000 to start a business. a I They borrow & of this amount.
Show that they still need $18000.
They provide the $18000 themselves in the ratio
Aida: Bernado : Christiano = 5: 4: 3.
Calculate the amount each of them provides.
b i Office equipment costs 35% of the $30000.
Calculate the cost of the equipment. ii Office expenses cost another $6500.
Write this as a fraction of $30 000.
Give your answer in its lowest terms. iii How much remains of the $30000 now?
c They invest $12500.
After one year this has increased to $15500.
Calculate this percentage increase.

Answers

Answer:

aida:$7500

Bernardo:$6000

Christiano :$4500

b.i $10500

b.ii 13/60

b.iii $13000

c. 24%

Given: AAED ≈ ABEC and
AC BD.
Prove: AABD≈ ABAC.
Note: quadrilateral properties are not permitted in this
proof.
Step
1
try
Statement
D
AAED ~ ABEC
AC BD
Type of Statement
E
с
Note: AC and DB are segments.
B

Answers

Side-Angle-Side (SAS) (SAS), The triangles are congruent if the included angles are also congruent and two sides of one triangle match two sides of another triangle.

How may the ABC def be demonstrated?

Side-Angle-Side (SAS) (SAS), The triangles are congruent if the included angles are also congruent and two sides of one triangle match two sides of another triangle.

The use of labels Triangle ABC is congruent to triangle DEF if the angles of triangles ABC and DEF are AB = DE, AC = DF, and A = D.

ABC=CDE: a) in accordance with the conditions BC=CD and AC=CE; b) BCA=m (DCE).

If ABC = CDE, then m(BAC) = m(DEC), and m(ABC) = m (CDE).

If m(BAC)=m(DEC), then AB || DE, or if m(ABC)=m(CDE), then AB || DE.

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10 students took 9 days to weed a school
compound. How long would it take 15
students to weed the same compound if
they weed at the same rate?

Answers

Answer:

It would take 15 students 6 days to weed the school compound

Step-by-step explanation:

This first step to solving this question is to break down the given rates.

We are told that 10 students take 9 days to weed the school compound. From here we can simplify this by figuring out how long it would take 1 student to weed the compound. Having less people would mean taking a longer time.

1 person is a 1/10 of 10 people. Since we have 10x less people, it should take 10x as long. Therefore it would take 1 person 9x10=90 days to weed a school.

Now the question asks how long it would take 15 people. 15 people is 15x as many as 1 person, so it should take 15x less time to weed the compound. 90/15 = 6

It would take 15 students 6 days to weed the school compound.

Similarly you could have just divided 9 by 1.5 as 15 is 1.5x10, but it is easier to explain the process using the above method.

Hope this helped!

Find the value of x and y so that the quadrilateral is a parallelogram.

(4x - 35° (y + 15)

(2y-5) (3x + 10)

X=

y =

Answers

Therefore, for x = 45 and y = 20, the quadrilateral is a parallelogram.

Define quadrilateral.

In geometry a quadrilateral is a four-sided polygon, having four edges and four corners.

What is a polygon?

A polygon is a closed polygonal chain made up of a limited number of straight-line segments and is a type of planar figure in geometry. A polygon is an area that is bordered by a bounding circuit, a bounding plane, or both.

We know opposite sides of a parallelogram are equal in length and parallel. Given opposite sides of a parallelogram are:

(4x - 35) and (3x + 10)

(y + 15) and (2y - 5)

Now, setting those opposite sides equal to each other:

4x - 35 = 3x + 10 = >x = 45

y + 15 = 2y - 5 => y = 20

Therefore, x = 45 and y = 20, the quadrilateral is a parallelogram.

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What should be added in the polynomial x³ 6x² 11x 8 so that it is completely divisible by X² 3x 2?

Answers

The number that should be added in the polynomial [tex]x^{3}-6x^{2} +11x+8[/tex]  , so that it is completely divisible by  [tex]x^{2} -3x+2[/tex] is  -14  .

What are Polynomials ?

A polynomial is defined as a type of algebraic expression where the exponents of all the variables is a whole number.

The exponents of the variables in any polynomial is a non-negative integer. A polynomial consists of constants and variables.

the polynomial expression is ⇒ [tex]x^{2} -3x+2[/tex], which can be written in factor form  as  : [tex](x-1)(x-2)[/tex] ,

that means the polynomial is divisible by both x = 1 and x = 2 ;

So , on substituting [tex]x=1[/tex] in the polynomial [tex]x^{3}-6x^{2} +11x+8[/tex] ,

we get , [tex]1^{3}-6\times1^{2} +11\times 1+8[/tex] = 14 ;

on substituting [tex]x=2[/tex] in the polynomial [tex]x^{3}-6x^{2} +11x+8[/tex] ,

we get , [tex]2^{3}-6\times2^{2} +11\times 2+8[/tex] = 14 ;

So , the remainder is 14  .

Therefore , -14 should be added in the given polynomial .

The given question is incomplete , the complete question is

What should be added in the polynomial x³ -6x² +11x +8 so that it is completely divisible by x² -3x +2 ?

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Explain why we rationalize the denominator of a radical expression.

Answers

Answer:

To rationalize the denominator means to eliminate any radical expressions in the denominator such as square roots and cube roots. The key idea is to multiply the original fraction by an appropriate value, such that after simplification, the denominator no longer contains radicals

help please with numbers 2-7 and please explain ur answer

Answers

2. A) 70 b) 67 c) 43 d) 43 e) 110 f) 137
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