SkyLineRush22 SkyLineRush22 17-05-2020 Mathematics contestada John’s rectangular backyard is (10x+4) feet long and (3x+2) feet wide. What is the area of his backyard? A. (30x^2+8) ft^2 B. (13x^2+19x+8) ft^2 C. (30x^2+32x+8) ft^2 D. (13x+6) ft^2