Respuesta :
5x+4x-8=28
9x-8=28
Move -8 to the other side
Sign changes from -8 to +8
9x-8+8=28+8
9x=28+8
9x=36
Divide both sides by 9 to get x by itself
9x/9=36/9
Answer: x=4
you add 5x and 4x, add 8 to both sides and divide to find x. x=4