The trick is to get rid of one variable by multiplication. In this example you can multiply y by -3 to eliminate all the y variables and then solve for x. Take the answer you obtain for x and replace it into one of the easier original equations to obtain y.

3y= -1/2x+2
y=-x+9
Now multiply the bottom equation by -3
-3y=3x-27
This will allow you to remove all the y variables and be left with just x.
3y=-1/2x+2
-3y=3x-27
Now solve for x
0=5/2x-25Add 25 to both sides to move it
25=5/2x
Multiply both sides by 2 to eliminate the fraction
50=5x
Now divide both sides by 5
x=10
Take an equation from the original set....
y=-x+9 and plug in 10
y=-10+9
y=-1


If you have anymore questions, I'd sure ask. I wouldn't want to lose my wheeler.

 

LOL thanks Jay - glad someone is watching my back. I haven't had math in like 4 years now LOL.

 

no problem thomez. calculus was the last math class i had. took it last semester and some how pulled an A. i'm just glad i don't have to take anymore math classes. i hate math.

 

I took Calc 1 and Calc 2 over at KSU my junior year of high school, that was my last math experience. I actually really like math just haven't needed to go farther than that.

 

Thomez, how hard is Calculus? I'm signing up for classes for my Jr. year in high school this week and need some advice. I've heard people say it is really hard. Is it?

 

calculus is a breeze compared to differential equations.

 

Uhhhhh...I was told there'd be NO math today. Imagine my surprise when I saw this post![img]i/expressions/face-icon-small-shocked.gif[/img]
I took two years of algebra in high school (back in the late 70's) and my 8th grade daughter is bringing home stuff I have NO clue about. I'm just happy I work at a 3rd & 4th grade school where I know all the answers! [img]i/expressions/face-icon-small-cool.gif[/img]

 

I've taken Algebra I and Geometry Honors so far in high school, and my brother in 6th grade is bringing home stuff I can't even figure out.

 

Sorry for the delay. I liked Calculus, it was pretty neat. I like 1 better than 2. 2 has very little real world application compared to 1, hence me enjoying 1 more. I did come up with a neat way to figure out square roots in my head while in Calc 2 though, probably the smartest thing I'll do in life. I guess I'm ready ta die [img]i/expressions/face-icon-small-smile.gif[/img]

 

You guys beat me to the punch! As a structural engineer I've had my fair share of the universal language. Good job helping the kid out and not just giving him the answer.[img]i/expressions/face-icon-small-wink.gif[/img]