Question

How do I solve this?

Answer 1

X+4

Explanation:

Area = l *b

x^2 + 13x + 36 = (X+9) * b

x^2 + 9x + 4x + 36 = (X+9) * b

X(X+9) + 4(X+9) = (X+9) * b

(X+4) (X+9) = (X+9) * b

b = (X+4)