SOLUTION: I am doing substitution method for equations. 2y+x=9, and x=3y-3. Do I start with putting the 2y-9 in 3y-3 because "x" has no base in 2y+x=9 except a 1 in x. Not sure on the ne

Algebra ->  Systems-of-equations -> SOLUTION: I am doing substitution method for equations. 2y+x=9, and x=3y-3. Do I start with putting the 2y-9 in 3y-3 because "x" has no base in 2y+x=9 except a 1 in x. Not sure on the ne      Log On


   



Question 690120:
I am doing substitution method for equations. 2y+x=9, and x=3y-3. Do I start with putting the 2y-9 in 3y-3 because "x" has no base in 2y+x=9 except a 1 in x. Not sure on the next way to go. My textbook does not show this type of problem.

Answer by checkley79(3341) About Me  (Show Source):
You can put this solution on YOUR website!
2y+X=9
X=3Y-3
2Y+(3Y-3)=9
5Y-3=9
5Y=9+3
5Y=12
Y=12/5 ANS.
X=3*12/5-3
X=36/5-3
X=36/5-15/5
X=21/5 ANS.
PROOF:
2(12/5)+21/5=9
24/5+21/5=9
45/5=9
9=9