SOLUTION: Substitution Problem: 2x + 3y= 1 and -x + 1/3y= 5 The answer in the book says (-4,3) but i didn't get that when i did it! Please explain.

Algebra ->  Expressions-with-variables -> SOLUTION: Substitution Problem: 2x + 3y= 1 and -x + 1/3y= 5 The answer in the book says (-4,3) but i didn't get that when i did it! Please explain.       Log On


   

Question 534977: Substitution Problem: 2x + 3y= 1 and -x + 1/3y= 5
The answer in the book says (-4,3) but i didn't get that when i did it! Please explain.
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Problem:
2x + 3y = 1
-x + 1/3y= 5
:
Multiply the 2nd equation by -9, then you have
2x + 3y = 1
9x - 3y = -45
---------------- addition eliminates y, find x
11x = -44
x = %28-44%29%2F11
x = -4
:
Find x using the 1st equation
2x + 3y = 1
2(-4) + 3y = 1
-8 + 3y = 1
3y = 1 + 8
3y = 9
y = 3