Alg-Substitution (check plz)

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k well i had to use substitution to find the point of intersection for these 2 equations

x-y=10
3x+y=11

i chose to substitute y in the first equation

my final answer was (-1/2 , 5) can someone clarify this, and if it's wrong, where'd i make a mistake?

In the first equation, y= x-10
put that into the second to get
3x + x-10=11
4x=21
x= 4.25
Then you can solve for y.

It's right! Congrats!

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