Exercise algebra.equations.quadratic.no-abc

Description
solve a quadratic equation without abc-formula

Derivation

x-7 == 2*sqrt 2 or x-7 == -2*sqrt 2

⇒ algebra.equations.coverup.onevar.minus-left

x == 7+2*sqrt 2 or x-7 == -2*sqrt 2

⇒ algebra.equations.coverup.onevar.minus-left

x == 7+2*sqrt 2 or x == 7-2*sqrt 2