Note: Solving a quadratic equation will result in two possible answers. Always make sure the values of x produce positive angles.
Angle c = 180 - 144 = 36 degrees
x^2 + 3x^2 + 36 = 180 degrees
4x^2 = 144
x^2 = 36
x = 6 take it from here !
Angle c = 180 - 144 = 36 degrees
x^2 + 3x^2 + 36 = 180 degrees
4x^2 = 144
x^2 = 36
x = 6 take it from here !