What is the solution of -2x plus 5 plus 21?

Answer 1

It has no solution. Equations have solutions, but expressions have not.

Had you asked, 'What is the solution to -2x + 5 + 21 = 0 ?', then I would reply,

'26 = 2x; therefore, x = 13',

is your solution.

You can check this, to see whether it is true.

The equation is clearly true, if we substitute 13 for x:

-2(13) + 5 + 21 = -26 + 5 + 21 = 0.

The moral is that equations are statements and may be true or false. Mere expressions are not statements, and they are therefore neither true or false.