Checking Solutions to Equations Examples Page 3

Is x = 2 a solution to the equation x² = 3x?

If we write down (2)² = 3(2), we're lying. Sorry. We'll never do it again.

Let's figure out, without lying, if x = 2 is a solution to the equation.

First evaluate the left-hand side expression for x = 2:

(2)² = 4

Then evaluate the right-hand side expression for x = 2:

3(2) = 6

Because 4 doesn't equal 6, x = 2 is not a solution to the equation x² = 3x. Ah. It feels oh-so-much better to arrive at the answer honestly, doesn't it?