SOLUTION: -3x+15y=3 -2x-5y=2

Algebra ->  Test -> SOLUTION: -3x+15y=3 -2x-5y=2       Log On


   

Question 948498: -3x+15y=3
-2x-5y=2
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

-3x%2B15y=3
-2x-5y=2

Solved by pluggable solver: Solve the System of Equations by Graphing



Start with the given system of equations:


-3x%2B15y=3

-2x-5y=2





In order to graph these equations, we need to solve for y for each equation.




So let's solve for y on the first equation


-3x%2B15y=3 Start with the given equation



15y=3%2B3x Add 3+x to both sides



15y=%2B3x%2B3 Rearrange the equation



y=%28%2B3x%2B3%29%2F%2815%29 Divide both sides by 15



y=%28%2B3%2F15%29x%2B%283%29%2F%2815%29 Break up the fraction



y=%281%2F5%29x%2B1%2F5 Reduce



Now lets graph y=%281%2F5%29x%2B1%2F5 (note: if you need help with graphing, check out this solver)



+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+%281%2F5%29x%2B1%2F5%29+ Graph of y=%281%2F5%29x%2B1%2F5




So let's solve for y on the second equation


-2x-5y=2 Start with the given equation



-5y=2%2B2x Add 2+x to both sides



-5y=%2B2x%2B2 Rearrange the equation



y=%28%2B2x%2B2%29%2F%28-5%29 Divide both sides by -5



y=%28%2B2%2F-5%29x%2B%282%29%2F%28-5%29 Break up the fraction



y=%28-2%2F5%29x-2%2F5 Reduce





Now lets add the graph of y=%28-2%2F5%29x-2%2F5 to our first plot to get:


Graph of y=%281%2F5%29x%2B1%2F5(red) and y=%28-2%2F5%29x-2%2F5(green)


From the graph, we can see that the two lines intersect at the point (-1,0) (note: you might have to adjust the window to see the intersection)