SOLUTION: I AM TRYING TO HELP MY DAUGHTER SOLVE THE FOLLOWING PROBLEM: x=3y 3y-6=2x Can you help me to explain how to solve this for her? Where do I begin? Thanks, Jan

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Question 26634: I AM TRYING TO HELP MY DAUGHTER SOLVE THE FOLLOWING PROBLEM:
x=3y
3y-6=2x
Can you help me to explain how to solve this for her? Where do I begin?
Thanks,
Jan
Answer by Earlsdon(6294) (Show Source):
You can put this solution on YOUR website!
You use "substitution to solve this system of equations.
1) x = 3y
2) 3y - 6 = 2x Substitute the 3y = x from equation 1) into equation 2) and solve for x.
x - 6 = 2x Subtract x from both sides.
-6 = x or x = -6 Now substitute this value of x = -6 into either of the two original equations and solve for y. Using equation 1)
-6 = 3y Divide both sides by 3.
-2 = y or y = -2
The solution is: (-6, -2) These are the x- and y-coordinates of the point of intersection of the two lines whose equations you started with.
See the graph below:Red line: x = 3y Green line: 3y - 6 = 2x