Respuesta :
Step-by-step explanation:
5x^2 +5x - x^2 + 3x -7 -12
or, 4x^2 + 8x - 19
This is the solution of this question..
Step-by-step explanation:
1st rearrange like terms
5x^2-x^2+5x+3x-7-12
then add/ subtract the rearranged like terms
4x^2+8x+19
finally there's no similar to simplify