first solve for one variable
solve for a in second eqatn
minus 3x both sides
a=17-3x
sub 17-3x for a in first equaiton
2(17-3x)+2x=18
34-6x+2x=18
34-4x=18
minus 34 both sides
-4x=-16
divide both sides by -4
x=4
sub back
a=17-3x
a=17-3(4)
a=17-12
a=5
a is 5
x=4
WORK SECTION (without thoughts)
2a+2x=18 to a+x=9
a+3x=17
a=17-3x
(17-3x)+x=9
17-2x=9
-2x=-8
x=4
a=17-3(4)
a=17-12
a=5
x=4
a=5
