I need help..

Question

A square and a rectangle have equal perimeters. One side of the rectangle is 4 cm long, and the area of the rectangle is 20cm squared . What is the area of the square.

Answer 1

A=lw for the area of the rectangle

20=l*4

l=5 cm,

you have a 4x5 rectangle

the perimeter is P=2*4+2*5=8+10=18 cm

P=4s for the perimeter of a square

18=4s

s=18/4=4.5 cm

A=s^2 for the area of a square

A=4.5^2=20.25 sq cm