# SOLUTION: Solve using the substitution method: x-y=5 x+2y=7 and please explain...thank you

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 Question 612882: Solve using the substitution method: x-y=5 x+2y=7 and please explain...thank youAnswer by jim_thompson5910(28598)   (Show Source): You can put this solution on YOUR website!Isolate x in the first equation x-y=5 to get x-y=5 x=5+y Now plug this into the second equation x+2y = 7 5+y+2y = 7 ... replace 'x' with 5+y (since x=5+y) *** Notice how this completely gets rid of 'x' in the second equation. This leaves us with y. Now solve for y 5+y+2y = 7 5+3y = 7 3y = 7-5 3y = 2 y = 2/3 Now that we know that y = 2/3, we can use this to find x. x = 5+y x = 5+2/3 x = 15/3+2/3 x = 17/3 So the solutions are x = 17/3 and y = 2/3 These solutions can be represented as the ordered pair (17/3, 2/3)