Algebra
posted by Samantha
How do I solve this For (x)?
(Do I just make x equal 1 or 2?) I’m suppose to solve the equation by elimination. (Can someone give me steps to solving it and I’ll try to do it and you guys check my work?)
7x9y=21
x18y=3

Scott
multiply the 1st equation by 2, then add the result to the 2nd equation
... this will eliminate y
solve the subsequent equation for x 
Samantha
I tried doing that but I think I went wrong somewhere because I did
7x9y=21
x18y=3
2•7=14
2•9=18
2•21=42
14x18y=42
x18y=3
And got x0y=3
x=45
...I know this is wrong, can someone help me 
Scott
you lost the minus sign on the 14
you did this ... 2•9=18
... the 9 was negative
... to give a positive 18 for cancelling with the 18 in the 2nd equation
should end up ... 15x = 45
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