Question

A rectangular piece of cardboard has a width of x and a length of y. When 15

centimeters is trimmed from the width and 25 centimeters is trimmed from the length,
which expressions describe the remaining piece of cardboard?
Classify each expression below according to whether it represents the perimeter, area, or
neither of these

Answer 1

Explanation:

Initial length of the cardboard was y cm, and width was x cm.

The new dimensions are:

length = (y - 25) cm

width = (x - 15) cm

Area of the new rectangle = length x width

= (y - 25) x (x - 15)

= (y - 25) (x - 15)
`cm^(2)`

Perimeter = 2 ( length + width)

= 2 ((y - 25) + (x - 15))

= 2(y - 25) + 2(x - 15)

Therefore:

2(x + y) - 40 is neither of these

2(x - 15) + 2(y - 25) is the perimeter

(x - 15)(y - 25) is the area

(x - 25)(y - 15) is neither of these

2(x - 15)(y - 25) is neither of these

2x + 2y - 80 is the perimeter

xy - 375 is neither of these

x + y - 40 is neither of these