use the substitution method to solve the system of equations. choose the correct ordered pair | y = 4x - 2 | y = x + 13

Accepted Solution

To use substitution, or the method of replacing variables with other expressions, numbers, variables, etc, notice how both the expressions are set equal to the value of y. This means that the expressions are equal to each other. Knowing this, you can replace the y value of one of the expressions. This would look like this:

Then, now that you only have one variable to worry about, you can solve for the x value:
First subtract x from both sides: 4x-x-2=x-x+13

Add -2 to both sides:

Then divide both sides by 3 to get that x=5.

Now that you know that x=5, you can plug this value into the x value into one of the equations to solve for y. Using y=x+13, when you plug 5 into x, you get y=18.

Therefore, knowing that x=5 and y=18, your final solution would be (5,18).