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2 years ago

Describe and correct the error a student made when solving the equation 7=-4(x+7)-3+2x. What is the correct solution?

Mathematics

1 answer:

olga55 [171]2 years ago

5 0

Answer:

7=-4(x+7)-3+2x

BODMAS

7=-4x-28-3+2x

7=-2x-31

7+31=-2x

x=38/2

x= -19

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Ashely is making $500 a week at her job. She receives a 20% pay raise. A year later she takes a 5% pay cut. How much money does

zheka24 [161]

Answer:

$570 a week

Step-by-step explanation:

Percentage Calculations

One tricky fact about percentages is that they are usually performed over the last computed quantity. It makes them non-additive. For example, a raise of 10% followed by a 10% some time later, is NOT a 20% of total raise

The question states Ashely is making $500 a week at her job and that she receives a 20% pay raise. After that raise she will make

$\$500*(1+20/100)=\$500(1.2)=\$600 \text{ a week}$

A year later she takes a 5% pay cut. We must be careful to take that percentage from the last earnings. She now makes

$\$600(1-5/100)=\$600(0.95)=\$570\ a\ week$

3 0

2 years ago

Find the solution of the system of equations -3x+8y=-5 and 6x+2y=-8

Simora [160]

Answer:

X=-1, y=-1

Step-by-step explanation:

-3x+8y=-5

6x+2y=-8

-6x+16y=-10

18y=-18

Y=-1

X=-1

7 0

2 years ago

A woman wishes to enclose a rectangular garden with fencing, using the side of her garage as one side of the rectangle. A neighb

Vika [28.1K]

Answer:

Width = 3.75 feet

Length = 9.75 feet

Step-by-step explanation:

Given:

Length of fencing = 27 feet

Find:

Dimensions of the garden

Computation:

Assume

Width = x

So,

Length = x + 6

2(L+B) = Perimeter

2(x + x + 6) = 27

2(2x + 6) = 27

4x + 12 = 27

4x = 15

x = 3.75

Width = 3.75 feet

Length = 3.75 + 6 = 9.75 feet

6 0

2 years ago

Point

ololo11 [35]

Your question is poorly formatted; However, the correct question is:

Point A ( 3 , 4 ) and point M (5.5,0) is the midpoint of point A and point B. Determine the coordinates of B

Answer:

The coordinates of B is (8,-4)

Step-by-step explanation:

Given

Point A ( 3 , 4 )

Point M (5.5,0)

Required

Determine B

Since, M is the midpoint;

We'll solve this question using the following formula;

$M(x,y) = (\frac{x_1 + x_2}{2},\frac{y_1 + y_2}{2})$

Where $(x,y) = (5.5,0)$ and $(x_1,y_1) = (3,4)$

Substitute values for x, y, x1 and y1 in the above formula;

This gives

$(5.5,0) = (\frac{3 + x_2}{2},\frac{4 + y_2}{2})$

By direct comparison, we have

$5.5 = \frac{3 + x_2}{2}$ and $0 = \frac{4 + y_2}{2}$

Solving $5.5 = \frac{3 + x_2}{2}$

Multiply both sides by 2

$11 = 3 +x_2$

Subtract 3 from both sides

$11- 3 = x_2$

$x_2 = 8$

Solving $0 = \frac{4 + y_2}{2}$

Multiply both sides by 2

$0 = 4 + y_2$

Subtract 4 from both sides

$0 - 4 = y_2$

$y_2 = -4$

Hence;

The coordinates of B is (8,-4)

3 0

2 years ago

The length of a new rectangular playing field is 6 yards longer than double the width. If the perimeter of the rectangular playi

Andru [333]

Answer:

width = 47

Length = 100

Step-by-step explanation:

The perimeter of the rectangle has the formula

P = 2(L + W)

P = 2L + 2W

Length = 6 yards longer than double it's width.

Mathematically,

length = 6 + 2W

We put this into the formula for perimeter

P = 2(6+2W)+2W

294 = 12+4W+2W

294 = 12+6W

Collect like terms

294-12 = 6W

282 = 6w

Divide through by 6

W = 282/6

W = 47

This is the width

Remember length = 6 + 2(W)

Length = 6+2(47)

= 6+94

= 100

Width = 47

L = 100

These are the dimensions

4 0

2 years ago