Question

Solve the linear system of equations using the linear combination method.

Answer 1

Hello!

4x - 9y = 20
2x - 6y = 16

You first need one of the variables have the same coefficient

We can do this by multiplying the second equation by 2

4x - 12y = 32

Subtract the equations to get rid of x

4x - 9y = 20
4x - 12y = 32

3y = -12

Divide both sides by 3

y = -4

Put y into one of the original equations

2x - 6(-4) = 16

Multiply

2x - -24 = 16

We you subtract a negative it is the same as addding

2x + 24 = 16

Subtract 24 from both sides

2x = -8

Divide both sides by 2

x = -4

The answers are x = -4 and y = -4

Hope this helps!