Explain your reasoning.
Let the area of the rectangle be A. Then, A = x^2 + 7x + 12
A = (x+3)(x+4) The factors are the dimensions of the rectangle.
Now, if we increase the dimensions by 3 meters, the new dimensions will be
(x+3+3) = (x+6) m and (x+4+3) = (x+7) m
The area of this rectangle, which I will call A2 will be
A2 = (x+6)(x+7)
= x^2 + 13x + 42 square meters