How do you solve these corresponding equations (will use the values of y and x to graph)

3x-y-=5 and x+3y=6

I've figured out how to solve 3x-y=5 by doing this:

3x-y=5

y=3x-5

But what about the other one? (x+3y=6)

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- November 4th 2008, 10:00 AMcnmath16Solving equations - to Graph!
How do you solve these corresponding equations (will use the values of y and x to graph)

3x-y-=5 and x+3y=6

I've figured out how to solve 3x-y=5 by doing this:

3x-y=5

y=3x-5

But what about the other one? (x+3y=6) - November 4th 2008, 11:39 AMearboth
- November 4th 2008, 05:46 PMeuclid2
this here is a common linear system.

there are three ways to solve, elimination, substitution, and by graphing

I will use substitution since it is easiest for this linear system

y=3x-5

x+3y=6

plug the value of y into the second equation

x+3(3x-5)=6

x+9x-15=6

10x=6+15

x=21/10

x=2.1

take that value and plug it into the other equation

y=3(2.1)-5

y=6.3-5

y=1.3

Thefore, the answer is (2.1,1.3)