Solve by using substitution. Express your answer as an ordered pair.

Question

Answer 1

x + 2y = -1

x = y + 5

For Substitution, we will need to plug in x = y + 5 into the first equation:

x + 2y = -1

(y + 5) + 2y = -1 substitute and then solve for y

3y + 5 = -1

-5 - 5

3y = -6 (divide by 3 on both sides)

y = -2

We have now found the y-coordinate in our ordered pair. Since y = -2, we can plug this into one of the original equations and solve for y. I recommend using x = y + 5 since it will give you a direct answer.

x = y + 5

x = -2 + 5

x = 3

So, the solution as an ordered pair is (3, -2).

Answer 2

Substitution is actually the easiest way to solve this system of equations!

We are told that x = y + 5, so just substitute y + 5 for the x in the other equation and solve.

x + 2y = -1 becomes y + 5 + 2y = -1. Combine like terms: 5 + 3y = -1 Subtract 5 from both sides:

3y = -6, divide by 3: y = -2. Then use that to find x. x = y + 5, so x = -2 + 5 = 3

Answer is (3, -2)

Check by substituting the values for x & y in both equations.