Unizor - Algebra - Equations - Problem 2
Channel: Zor Shekhtman on UNIZOR Education
Date: 08/09/2011

Welcome to UNIZOR.COM http://www.unizor.com.
Cautiously using invariant and not invariant transformations, solve equations: 
2*√(X + 4) - 10 = 0;
(√(X + 4))/2 - 10 = 0;
(√(X + 4))/2 - 10*√(X + 1) = 0;

Note: Transformation T(X): X → X^2 is not invariant and in some cases can add wrong solutions to an original equation. It cannot loose real solutions, however. So, it is admissible to use it but every solution of a transformed equation must be checked against an original one.