Question

Solve the system of linear equations using linear combination.

3a + 6b = 45

2a – 2b = –12

Which is the solution to the system?

Answer 1

(1,7)

Step-by-step explanation

The given equations are:

1st: 3a + 6b = 45

and

2nd:2a – 2b = –12

Multiply the second equation by 3,

3rd: 6a – 6b = –36

Add the first and third equations.

6a+3a+6b-6b=45+-36

Simplify,

9a=9

a=1

Put a=1 in the second equation:

2(1) – 2b = –12

-2b=-12-2

-2b=-14

b=7