SOLUTION: please help me solve y=2x+7 3x-y=-9 i have tried to solve it but cant get it right and i dont know what im doing wrong

Algebra ->  Expressions-with-variables -> SOLUTION: please help me solve y=2x+7 3x-y=-9 i have tried to solve it but cant get it right and i dont know what im doing wrong      Log On


   



Question 244256: please help me solve
y=2x+7
3x-y=-9
i have tried to solve it but cant get it right and i dont know what im doing wrong

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
y=2x+7
3x-y=-9
add y to both sides
add 9 to both sides
3x+9=y
equate the two
3x+9=2x+7
substract 2x from both sides
x+9=7
substract 9 from both sides
x=-2
y=2(-2)+7
y=3
check
3(-2)-3=-9
-6-3=-9
-9=-9