Exercise algebra.equations.quadratic.no-abc

Description
solve a quadratic equation without abc-formula

Derivation

3*x^2+12*x-36 == 12*x
algebra.equations.quadratic.cancel
3*x^2-36 == 0
algebra.equations.quadratic.no-lin
3*x^2 == 36
algebra.equations.coverup.times
x^2 == 12
algebra.equations.coverup.power
x == sqrt 12 or x == -sqrt 12
algebra.equations.quadratic.simpler-sqrt
x == 2*sqrt 3 or x == -2*sqrt 3