Exercise algebra.equations.quadratic.no-abc

Description
solve a quadratic equation without abc-formula

Derivation

0 == x^2-3*x-40

⇒ algebra.equations.linear.flip

x^2-3*x-40 == 0

⇒ algebra.equations.quadratic.nice-factors

(x+5)*(x-8) == 0

⇒ algebra.equations.quadratic.product-zero

x == -5 or x == 8