You can
put this solution on YOUR website!I'm assuming that the +10 in the third equation is =10
A) add the first and third equations to eliminate x ... -y+3z=13
B) add the second and 2 times third to eliminate x ... -3y+5z=27
add -3 times A) to B) to eliminate y ... -4z=-12 ... z=3
-y+3(3)=13 ... -y+9=13 ... y=-4
x+(-4)+2(3)=3 ... x+2=3 ... x=1