x-2y = 10
3x-5y = 27 multiply first equation by -3 to get:
-3x + 6y = -30 now add the bottom two equations (this will 'ELIMINATE' the 'x' variable)
y = -3
now use this value of y in one of the eqautions to find x
x - 2(-3) = 10
Solve the second one similarly.....