Question

What number should be added to the expression x2+2x to change it into a perfect square trinomial?

Answer 1

Answer: x² + 2x + 1

Step-by-step explanation: To make this a perfect square trinomial, we just take half the coefficient of the middle term squared and add it.

So that's half of 2 which is 1 and when we square 1, we still have 1.

So our perfect square trinomial is x² + 2x + 1