SOLUTION: I have tried this over and over and can't figure out what I did wrong. I know that it is a simple mistake. Here we go: I am solving for both x & y. 5x+y=54 4x-y=36 I combined

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Question 7629: I have tried this over and over and can't figure out what I did wrong. I know that it is a simple mistake. Here we go: I am solving for both x & y.
5x+y=54 4x-y=36
I combined like terms and then (divided both sides by 9) Answer x=10
How do I solve for y?
What am I missing?
Answer by prabhjyot(164) About Me  (Show Source):
You can put this solution on YOUR website!
5x+y=54 ---->(1)
4x-y=36 --->(2)
Adding both the equations
5x +y = 54
4x -y = 36
-----------
9x +0 = 90
we get
9x=90
x=90/9
x=10
now substitute value of x in any of the two equation
lets plugin the value of x in equation (1)
5(10) +y= 54
50 +y =54
y= 54-50
y=4
so x=10 and y=4