Question

The length of a rectangle is twice its width the area is 50 what is the perimeter

Answer 1

L = 2w
a = 50
a = L · w
50 = 2w · w
50 = 2w²
25 = w²
5 = w
 
L = 2w
L = 2(5)
L = 10
w = 5

L + L + w + w = perimeter or 2L + 2w = perimeter
10 + 10 + 5 + 5 = perimeter or 2(10) + 2(5) = perimeter
perimeter = 30