Question

3x - y = 7 y = 2x - 2

Answer 1

Answer:

x = 9

Step-by-step explanation:

1) Subsitute! You have to replace y with 2x - 2 in 3x -y = 7, b/c they already gave you the equation for y (in the second part: y = 2x - 2)

 So, your equation would look like this : 3x - (2x - 2) = 7

3) Solve suing PEMDAS!

There's a negative outside the parenthesis of 2x -2 -> - (2x-2). Multiply the negative individually inside the parenthesis so you will get (-2x + 2)

3x - 2x - 2 = 7    subtract the same variable; x

1x - 2 = 7            you don't need to put 1 to x, only if you want!

    + 2  + 2           add 2 on both sides

x = 9