Question

Please help me. Don't ignore it. Thank you

Answer 1

Answer:

See below.

Step-by-step explanation:

The area of the smaller rectangle = x(x - 4)

The area of the larger one = 3x(x - 2).

So we have

x(x - 4) + 3x(x - 2) = 36

x^2 - 4x + 3x^2 - 6x - 36 = 0

4x^2 - 10x - 36 = 0

Dividing through by 2:

2x^2 - 5x - 18 = 0  <-------- as required.

Solving for x:

2x^2 - 5x - 18 = 0

(2x - 9)(x  + 2 ) = 0

2x = 9   or  x + 2 = 0

x = 4.5          (we ignore the other result, x = -2).

So AB = 4.5 cm  Answer.