SOLUTION: Solve by rearranging the equations first. Then use the multiplication principle and then use the elimination method: 3x=8y+11 x+6y-8=0 I know rearranged they are: 3x-8y=

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: Solve by rearranging the equations first. Then use the multiplication principle and then use the elimination method: 3x=8y+11 x+6y-8=0 I know rearranged they are: 3x-8y=      Log On


   

Question 373989: Solve by rearranging the equations first. Then use the multiplication principle and then use the elimination method:
3x=8y+11
x+6y-8=0
I know rearranged they are:
3x-8y=11
x+6y=8
But then I would need to take -3 times (3x-8y=11)
After figuring it out my answer is y=-35 over 26. But I do not think I am right!! Please help!!
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

Start with the given system of equations:
system%283x-8y=11%2Cx%2B6y=8%29


-3%28x%2B6y%29=-3%288%29 Multiply the both sides of the second equation by -3.


-3x-18y=-24 Distribute and multiply.


So we have the new system of equations:
system%283x-8y=11%2C-3x-18y=-24%29


Now add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:


%283x-8y%29%2B%28-3x-18y%29=%2811%29%2B%28-24%29


%283x%2B-3x%29%2B%28-8y%2B-18y%29=11%2B-24 Group like terms.


0x%2B-26y=-13 Combine like terms.


-26y=-13 Simplify.


y=%28-13%29%2F%28-26%29 Divide both sides by -26 to isolate y.


y=1%2F2 Reduce.


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3x-8y=11 Now go back to the first equation.


3x-8%281%2F2%29=11 Plug in y=1%2F2.


3x-4=11 Multiply.


3x=11%2B4 Add 4 to both sides.


3x=15 Combine like terms on the right side.


x=%2815%29%2F%283%29 Divide both sides by 3 to isolate x.


x=5 Reduce.


So the solutions are x=5 and y=1%2F2.


Which form the ordered pair .


This means that the system is consistent and independent.


If you need more help, email me at jim_thompson5910@hotmail.com

Also, feel free to check out my tutoring website

Jim