SOLUTION: Please help me solve the system of equations by the substitution method: {{{2y+x=9 and x=3y-3}}}

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Question 811725: Please help me solve the system of equations by the substitution method:
2y%2Bx=9+and+x=3y-3
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

2y%2Bx=9 ........eq.1
x=3y-3.....eq.2
__________________________
2y%2Bx=9 ........eq.1......substitute x from eq.2
2y%2B3y-3=9.....solve for y
5y=9%2B3
5y=12
y=12%2F5
highlight%28y=2.4%29
now, go back to x=3y-3.....eq.2, substitute 2.4 for y and solve for x
x=3%2A2.4-3.....eq.2
x=7.2-3
highlight%28x=4.2%29