Question

The diagram shows a rectangle. The area of the rectangle is 310 m². Work out the value of w when 5x-9 is the length and 3x+7 is the another length​

Answer 1

w = 10

Explanation:

First we take the two values for the breadth of the rectangle

So:

5x - 9 = 3x + 7

now we solve this equation as follows:

5x - 3x = 9 + 7

2x = 16

x = 8

now that we have found the value for x, we can substitute it in the equation, 5x - 9,or in the equation, 3x + 7.

when we substitute x in any of these equations, we get

5(8) - 9 = 31

3(8) + 7 = 31

now that we have the value for the breadth we can form the following equation:

31 × w = 310

31w = 310

w = 310/31 = 10

Answer 2

10

Explanation:

Firstly, we find the value of X

since 5X-9 and 3X+7 are lenghts

5X-9= 3X+7

5X-3X= 7+9

2X = 16

dividing bothsides by 2

2X/2= 16/2

X = 8

Hence,

5X-9= 5(8)-9= 40-9 = 31

3X+7=3(8)+7= 24+7= 31

To find the width

Area= lenght×width

310= 31×w

31w= 310

w= 310/31

W= 10