Solve each system using substitution.
-x^2-x+19=y
x=y+80

sub since -x^2+x+19=y x=-x^2+x+19+80 x=-x^2+x+99 0=-x^2+99 x^2=99 x=3√11

x=y+80
3√11=y+80
minus 80 both sides
-80+3√11=y

x=3√11
y=-80+3√11

solution
(x,y)
(3√11,-80+3√11)

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