You want to start by cancelling equal terms on both sides of the equation which means getting rid of both 8's. You are left with (-7)-(7)=7+(-4).
From here you want to solve both sides meaning adding -7-7 because both terms are negative they will combine, and the other side which is -7+4. They are opposite terms so you will subtract. This leaves you with -14=3 which is false.
