The davidson family wanted to expand its rectangular patio, which currently measures 15 ft by 12 ft. they want to extend the length and width the same amount to increase the total area of the patio by 160 ft^2. which quadratic equation best models the situation?
a. (15)(12)+(x)(x) = (15)(12) + 160
b. (15x)(12x)=(15)(12) + 160
c. 2(15+x) + 2(12+x) = (15)(12) + 160
d. (15 + x)(12 + x) = (15)(12) + 160