A rectangular garden has a walk around it of a width x. The garden is 20 ft by 15 ft. Write a function representing the combined area, A(x), of the garden walk. Write as a polynomial in standard form.

Question

A rectangular garden has a walk around it of a width x. The garden is 20 ft by 15 ft. Write a function representing the combined area, A(x), of the garden walk. Write as a polynomial in standard form. 
Use the function you came up with in the previous question to find the combined area if the walkway is 3ft. Write a sentence that gives your labeled answer.

Steve · Answer

since there is a walkway on both sides, each dimension is increased by 2x. A(x) = (20+2x)(15+2x)