Answer:
Explanation:
A=2B
AreaA= Area of a rectangle=Base* height = base (12-x)*height(4) = 48-4x
AreaB = Area of rectangle=base(x) *Height(x) =x^2
Since A=2B
48-4x =2x^2
Divide both sides of the equation by 2
24-2x=x^2
Put everything all on one side
X^2-2x-24=0
(x+4)(x-6)=0
X=-4 and x=6
Only x makes sense since it’s not negative or else your base or one of your sides would be negative
So x=6