SOLUTION: Use the substitution method to solve th linear system 5x-4y=50 10x+y=10 i keep getting fraction answers.. Please Help~

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Question 699361: Use the substitution method to solve th linear system
5x-4y=50
10x+y=10
i keep getting fraction answers.. Please Help~
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
When trying substitution, look for the variable without a number in front of it.
Substitution works well when one of the variables' coefficients is 1,
as in the invisible coefficient in front of the y in 10x%2By=10.
Then, you "solve" for that variable in that equation,
to get an expression for that variable in terms of the other variable:
10x%2By=10 --> y=10-10x
Then you substitute the expression found for the variable in the other equation.
5x-4y=50 --> 5x-4%2810-10x%29=50 --> 5x-40%2B40x=50 --> 45x-40=50 --> 45x=50%2B40 --> 45x=90 --> x=90%2F45 --> highlight%28x=2%29
The next step is substituting 2 for x in y=10-10x to get
y=10-10%2A20 --> y=10-20 --> highlight%28y=-10%29

For system%285x-4y=50%2C10x%2By=10%29 ,
if you try to use substitution a different way, you end up with fractions.
It is possible to do it, but I would not try it,
because I am likely to make some mistake as the calculations get complicated.