We know that all angles added together equal to 180.
Let y represent the missing angle
Angle 1: x^2
Angle 2: 90-x
x^2+(90-x)+(y)=180
y=180-x^2-90+x
y=-x^2+x+90
y=(x+9)(x-10)
Therefore, y could be 10 (because -9 is not an existant/possible solution since it is negative)
Hope I helped :)
