I'm so confused about solving by substitution.

Consider the following pair of equations:

y = - 2x + 8

y = x - 1

Explain how you will solve the pair of equations by substitution. Show all the steps and write the solution in (x, y) form.

x = 3

y = 2

Step-by-step explanation:

Given

y = - 2x + 8

y = x - 1

Substitute x - 1 for y in the first equation

We have

y = - 2x + 8

x - 1 = - 2x + 8

Add 1 to both sides to eliminate 1 on the left side

x - 1 + 1 = - 2x + 8 + 1

x = - 2x + 9

Add 2x to both sides to eliminate 2x on the right side

x + 2x = - 2x + 2x + 9

3x = 9

Divide both sides by 3 to isolate x

3x/3 = 9/3

x = 3

Now substitute 3 for x in either equations to get y

Using the second equation, we have

y = x - 1

y = 3 - 1

y = 2

x = 3 and

y = 2