Solve 7b 3 - 4b = 3 - 3 (b 4)
7b + 3 - 4b = 3 - 3(b + 4)3b + 3 = 3 - 3b - 123b + 3b = 3 - 12 - 3 = -126b = -12b = -12/6 = -2b = -2