SOLUTION: 15y=6+15x 15x-20y=-7 I really need help and step by step instructions thank you. I need it by the 14th please!!

Algebra ->  Coordinate Systems and Linear Equations -> SOLUTION: 15y=6+15x 15x-20y=-7 I really need help and step by step instructions thank you. I need it by the 14th please!!      Log On


   

Question 384329: 15y=6+15x
15x-20y=-7

I really need help and step by step instructions thank you. I need it by the 14th please!!
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
15y=6%2B15x Start with the first equation.


15y-6=15x Subtract 6 from both sides.


15x=15y-6 Rearrange the equation.


15x-20y=-7 Move onto the second equation.


15y-6-20y=-7 Replace '15x' with '15y-6'. This is possible because 15x=15y-6


-5y-6=-7 Combine like terms on the left side.


-5y=-7%2B6 Add 6 to both sides.


-5y=-1 Combine like terms on the right side.


y=%28-1%29%2F%28-5%29 Divide both sides by -5 to isolate y.


y=1%2F5 Reduce.


15x=15y-6 Go back to the equation where we isolated 15x


15x=15%281%2F5%29-6 Plug in y=1%2F5


15x=3-6 Multiply and reduce.


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


x=%28-3%29%2F%2815%29 Divide both sides by 15 to isolate x.


x=-1%2F5 Reduce.


So the solutions are x=-1%2F5 and y=1%2F5


which form the ordered pair


So the system is consistent and independent.