Exercise algebra.equations.quadratic.no-abc
Description
solve a quadratic equation without abc-formula
Derivation
x^2+2*x+1 == 9
⇒ algebra.equations.quadratic.left-square(x+1)^2 == 9
⇒ algebra.equations.coverup.powerx+1 == 3 or x+1 == -3
⇒ algebra.equations.coverup.onevar.plusx == 2 or x+1 == -3
⇒ algebra.equations.coverup.onevar.plusx == 2 or x == -4