Exercise algebra.inequalities.quadratic

Description
solve a quadratic inequation

Derivation

0 == x^2+3*x-4

⇒ algebra.equations.linear.flip

x^2+3*x-4 == 0

⇒ algebra.equations.quadratic.nice-factors

(x-1)*(x+4) == 0

⇒ algebra.equations.quadratic.product-zero

x == 1 or x == -4