Question

{3x-7y=5
{9x-2y=7
son método de igualacion

Answer 1

3x=5+7y
x= (5+7y)/3
9x=7+2y
x=(7+2y)/9
Igualando 
x=x
(5+7y)/3=(7+2y)/9
9(5+7y)/3=7+2y
3(5+7y)=7+2y
15+21y=7+2y
21y-2y=7-15
19y=-8
y=-8/19
3x-7(-8/19)=5
3x=5-7(8/19)
3x=5-56/19
3x= (95-56)/19
3x=39/19
x=13/19