+36916 From 1st equation y = 20 - 2x sub this into 2nd eqaution
x^2 + x (20-2x) =47
-x^2 +20x - 47 = 0 quadratic equation shows x = 10 +-sqrt 53
sub into one of the equations (the first is easiest ) to find y = -2sqrt53 when x = 10 + sqrt 53
and y = 2 sqrt53 when x = 10 - sqrt53
