Question 71115
-3(10X-3)+10(3X-3)=X-7
-30X+9+30X-30=X-7
-30X+30X-X=-7-9+30
-X=14
X=-14
PROOF
-3(10*-14-3)+10(3*-14-3)=-14-7
-3(-140-3)+10(-42-3)=-21
-3*-143+10*-45=-21
429-450=-21
-21=-21