Question

Which of the following expressions are perfect-square trinomials? Check all of the boxes that apply.

x2 – 16x – 64

4x2 +12x + 9

x2 + 20x + 100

x2 + 4x + 16

Answer 1

Perfect-square trinomials:
- 4x^2 + 12x + 9 = (2x + 3)^2
- x^2 + 20x + 100 = (x + 10)^2

Not perfect squares:
- x^2 − 16x − 64 (would need constant +64 for (x − 8)^2)
- x^2 + 4x + 16 (would need constant 4 for (x + 2)^2)