What is the difference? (-4x + 3) - (7x - 3x^2 - 1)

4x-6y-7x+8 combine like terms: - 3x-6y+8 If all you want to do is simplify, then that is the final answer. However if we want to evaluate that when x=5 and y=2, we substitute (5) in place of x and (2) in place of y - 3x-6y+8 - 3 (5) - 6 (2) + 8 Then do all the operations: - 15-12+8 - 19