6
Step-by-step explanation:
area of 1 rectangle= area of 2 rectangle
x(x+4) = (2x+3)(x-2)
x² + 4x = 2x² - 4x + 3x - 6
x² + 4x = 2x² - x - 6
x² + 4x - 2x² + x + 6 = 0
-x² + 5x + 6 = 0
x² - 5x - 6 = 0
x² - 6x + x - 6 = 0
x(x - 6) + 1(x - 6)=0
(x+1)(x-6)=0
x = 6,-1
