Answer:
the answer of question number 4 is : (x+4)
Just set it equal to zero and solve using the quadratic equation.
So we're looking at two rectangles, one cut out of the other, so all you do is find the area of the big one, base times height equals area, minus the area of the small one, base times height equals area. So the equation you have to solve for is this,
Area=(12.6X14)-(3X8.4)