Exercise algebra.equations.quadratic.no-abc
Description
solve a quadratic equation without abc-formula
Derivation
![](http://ideas.cs.uu.nl/images/external.png)
0 == x^2-3*x-40
⇒ algebra.equations.linear.flipx^2-3*x-40 == 0
⇒ algebra.equations.quadratic.nice-factors(x+5)*(x-8) == 0
⇒ algebra.equations.quadratic.product-zerox == -5 or x == 8