SOLUTION: So, my question on homework is how to do this substitution equation. The homework question is: 5.) Solve by substitution : y = -3x and 2x - 3y = 22 Please help, and than

Algebra ->  Linear-equations -> SOLUTION: So, my question on homework is how to do this substitution equation. The homework question is: 5.) Solve by substitution : y = -3x and 2x - 3y = 22 Please help, and than      Log On


   

Question 836687: So, my question on homework is how to do this substitution equation.
The homework question is:
5.) Solve by substitution : y = -3x and 2x - 3y = 22
Please help, and thank you in advance.

Found 2 solutions by josgarithmetic, nerdybill:
Answer by josgarithmetic(39621) About Me  (Show Source):
You can put this solution on YOUR website!
So do it! What is stopping you? You have what to substitute.

2x-3%28-3x%29=22
You can do the rest; right?

Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
y = -3x and 2x - 3y = 22
.
Using:
y = -3x
We "substitute" the value of 'y' with '-3x' (since they are equal) into:
2x - 3y = 22
2x - 3(-3x) = 22
2x + 9x = 22
11x = 22
x = 2 (answer for x)
.
Answer for y, we substitute the above into:
y = -3x
y = -3(2)
y = -6 (answer for y)
.
Solution: (x,y) = (2, -6)