Question 14235
4x + 3x -5 = 27

The solution of the equation is a number that why if you substitute it to equation you got true statement. 

Let's do. Substitute -2 to 4x + 3x -5 = 27.
4x + 3x -5 = 27
4(-2)+3(-2)-5=27
-8+(-6)-5=27
-19=27 (is it true statement? of course it's false). Thus, -2 is not the solution of this equation.

OK