Each side of a square is increased 5 inches. When this happens, the area is multiplied by 25. How many inches in the side of the original square?

Answer 1

s^2 = area of the original square

(s+5)^2 = 25s^2

s^2 + 10s +25 = 25s^2

24s^2 - 10s -25 = 0

(6s + 5)(4s -5) = 0

s = -5/6, 5/4 = 1.25 inch for each side of the original square

It's area was 1.25^2 = 1.5625 in^2

s+5 = increased side

(s+5)^2 = (1.25+5)^2 = (6.25)^2 = 39.0625 in^2

1.5625 x 25 = 39.0625