Exercise algebra.equations.quadratic.no-abc
Description
solve a quadratic equation without abc-formula
Derivation
![](http://ideas.cs.uu.nl/images/external.png)
x^2-7 == 0
⇒ algebra.equations.quadratic.no-linx^2 == 7
⇒ algebra.equations.coverup.powerx == sqrt 7 or x == -sqrt 7
Description
solve a quadratic equation without abc-formula