Exercise algebra.equations.quadratic.no-abc

Description
solve a quadratic equation without abc-formula

Derivation

x^2+12*x == 2*x^2
algebra.equations.quadratic.move-left
-x^2+12*x == 0
algebra.equations.quadratic.common-factor
-x*(x-12) == 0
algebra.equations.quadratic.product-zero
x == 0 or x == 12