Question

The length and width of a rectangle are 7 cm and (x-8) cm respectively. Find the value of x if the area of the rectangle is 42 cm(square)

Answer 1

so it would be 7 (x - 8) = 42
divide by 7 on both sides ______ ___
7 7
(x - 8) = 6
+8 = +8
x = 14 cm

Answer 2

given length l=7
width w=x-8
area=42
area=wl
42=7(x-8)
42=7x-56
7x=98
x=98/7
x=14