Exercise algebra.equations.quadratic.no-abc
Description
solve a quadratic equation without abc-formula
Derivation
![](http://ideas.cs.uu.nl/images/external.png)
3*x^2+12*x-36 == 12*x
⇒ algebra.equations.quadratic.cancel3*x^2-36 == 0
⇒ algebra.equations.quadratic.no-lin3*x^2 == 36
⇒ algebra.equations.coverup.timesx^2 == 12
⇒ algebra.equations.coverup.powerx == sqrt 12 or x == -sqrt 12
⇒ algebra.equations.quadratic.simpler-sqrtx == 2*sqrt 3 or x == -2*sqrt 3