Question

The length of a rectangle is 7cm more than twice the width. When just the width is tripled, the perimeter of the resulting rectangle is 74cm. What are the original dimensions of the rectangle?

Answer 1

Length = 27cm

Width = 10cm

Explanation:

Let the length of the rectangle be x

Let the width be y

If the length of a rectangle is 7cm more than twice the width, then;

x = 2y + 7

Since P = 2(x+y)

P = 2(2y+7+y)

P = 2(3y+7)

P = 6y+14

If the width is tripled, P = 74

74 = 6y+14

6y = 74-14

6y = 60

y = 10

Since x = 2y+ 7

x = 2(10) + 7

x= 20+7

x = 27

Hence the original dimension is 27cm by 10cm