Solve for a and b? 10 points?

Question

5a - 2b = 8
3a - 7b = -1

Please help  

Answer 1

Gven equations are 5a-2b = 8 ---> (1)

3a-7b = -1 ---> (2)

Multple to each side of equation (1) by negitive 3.

-15a+6b = -24 ---> (3)

Multple to each side of equation (2) by 5.

15a-35b = -5 ---> (4)

To eliminate the a value add the equations (3)&(4).

-15a+6b = -24

15a-35b = -5

_____________

-29b = -29

Divide to each side by negitive 29.

-29b/-29 = -29/-29

b = 1

Substitute the b value in (1).

5a-2 = 8

Add 2 to each side.

5a = 10

Divide to each side by 5.

a = 2

Solution a = 2,b = 1.