Exercise algebra.equations.quadratic.no-abc

Description
solve a quadratic equation without abc-formula

Derivation

x^2+12*x+36 == 16

⇒ algebra.equations.quadratic.left-square

(x+6)^2 == 16

⇒ algebra.equations.coverup.power

x+6 == 4 or x+6 == -4

⇒ algebra.equations.coverup.onevar.plus

x == -2 or x+6 == -4

⇒ algebra.equations.coverup.onevar.plus

x == -2 or x == -10