Question 68696
7X+3(2X+5)=10X+17
7X+6X+15=10X+17
13X-10X=17-15
3X=2
X=2/3
PROOF
7*2/3+3(2*2/3+5)=10*2/3+17
14/3+3(4/3+5)=20/3+17
14/3+3(4/3+15/3)=20/3+51/3
14/3+3(4+15)/3=71/3
14/3+(4+15)=71/3
14/3+19=71/3
14/3+57/3=71/3
71/3=71/3