SOLUTION: Hi! I'm working on my algebra homework and came across a problem that I'm not sure how to solve. The problem is: Eight times a number plus five times another number is -13. The sum

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Question 928272: Hi! I'm working on my algebra homework and came across a problem that I'm not sure how to solve. The problem is: Eight times a number plus five times another number is -13. The sum of the 2 numbers is 1. What are the numbers?
I've already figured out the 2 equations which are: 8x+5y=-13 and x+y=1 .
However, I have major trouble with solving problems using substitution, and the method of elimination cannot be used. I don't know if Im supposed to get x or y alone, or if it even matters. Please help me out. Thank you!
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
Take your pick. Choose an equation and solve for a variable in terms of the other variable. Neither equation is right or wrong to choose first; neither variable is right or wrong to solve as formula first.

An easy way to begin, is take the simpler equation and solve for either variable in terms of the other variable, and then substitute into the other equation.
x=1-y
-
8%281-y%29%2B5y=-13
8-8y%2B5y=-13
8-3y=-13
8%2B13=3y
3y=21
highlight_green%28y=7%29
Do the rest.