SOLUTION: Please help me solve this by substitution x+6y=9 2x+5y=4

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Question 1002707: Please help me solve this by substitution
x+6y=9
2x+5y=4
Found 2 solutions by Fombitz, person24:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
From eq. 1,
x=-6y%2B9
Substituting into eq. 2,
2%28-6y%2B9%29%2B5y=4
-12y%2B18%2B5y=4
-7y=-14
y=2
Then,
x=-6%282%29%2B9
x=-12%2B9
x=-3

Answer by person24(13) About Me  (Show Source):
You can put this solution on YOUR website!
x+6y=9
2x+5y=4
okay first get one variable by itself on the firs equation. I prefer to start with x but you can start with y if you would like.
x+6y=9
x=9-6y
Now you substitute x for 9-6y in the second equation...
2(9-6y)+5y=4
distribute
18-12y+5y=4
combine like terms
18-7y=4
-7y=-14
divide -7
y=2
woot!
now we need x
so in the first equation substitute y for 2
x+6y=9....
x+6(2)=9
multiply
x+12=9
subtract
x=-3
yay!
now check your work for x=-3 and y=2 in the first equation (or whichever you like it doesn't mater)

x+6y=9
(-3)+6(2)=9????
-3+12=9???
9=9 :D