Problem Solving (PS) | Re: The sides of rectangle A are each multiplied by x to form rectangle B

So we have three rectangles:
Let, Rectangle A = a * b
then, Rectangle B = ax * bx =\(x^2 * a * b\)
then, Rectangle C = ay * by =\(y^2 * a * b\)

Given,
When multiplied by x, the area of rectangle A equals 10 = x * a * b = 10 ->(a)
when multiplied by y, the area of rectangle A equals 5 = y * a * b = 5 ->(b)

The difference in the area between rectangle B and C is 300 =\(x^2*a*b - y^2*a*b = 300\) =>\((x^2 - y^2) (a * b) = 300\) =>\( (x + y)(x - y)(a * b) =\)
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