Exercise algebra.equations.quadratic.no-abc
Description
solve a quadratic equation without abc-formula
Derivation
3*x^2-6*x-9 == 0
⇒ algebra.equations.quadratic.scalex^2-2*x-3 == 0
⇒ algebra.equations.quadratic.nice-factors(x+1)*(x-3) == 0
⇒ algebra.equations.quadratic.product-zerox == -1 or x == 3