SOLUTION: Can someone please show me how to work and graph the following linear equation... x + y = 150 5x + 8y = 930 Thank you very much!

Algebra ->  Linear-equations -> SOLUTION: Can someone please show me how to work and graph the following linear equation... x + y = 150 5x + 8y = 930 Thank you very much!      Log On


   

Question 149213: Can someone please show me how to work and graph the following linear equation...
x + y = 150
5x + 8y = 930
Thank you very much!
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.x%2By=150
2.5x%2B8y=930
Multiply eq. 1 by (-5) and add the two equations together.
-5%28x%2By%29%2B5x%2B8y=-5%28150%29%2B930
-5x%2B5x-5y%2B8y=-750%2B930
3y=180
highlight%28y=60%29
From eq. 1,
1.x%2By=150
x%2B60=150
highlight%28x=90%29
Graphing, first put both equations into slope intercept form, y=mx%2Bb
1.x%2By=150
1.y=-x%2B150
Slope, m=-1.
y-intercept is 150.
x-intercept is 150.
+graph%28+300%2C+300%2C+-25%2C+225%2C+-20%2C+180%2C+-x%2B150%29+
2.5x%2B8y=930
2.8y=-5x%2B930
2.y=%28-5%2F8%29x%2B465%2F4
Slope, m=-5/8.
y-intercept is 465/4=116.25.
x-intercept is 186.
+graph%28+300%2C+300%2C+-25%2C+225%2C+-20%2C+180%2C+-x%2B150%2C%28-5x%2B930%29%2F8%29+