Suppose a classmate claims that the differnece between (x+2) 2 and (x2+4) mist be 0. Is your classmate correct? Choose the best explanation.

The two are not the same, even if you set x = - 2, the second becomes 8, not 0 (your option B is in error as it did not square the negative as it should have).

If you subtract one from the other, you get:

(x + 2) ² - (x² + 4)

(x² + 4x + 4) - x² - 4

4x