Question

Check all polynomials that are perfect square trinomials:

9x2 − 6x + 1

36b2 − 24b + 8

16x2 + 24x + 9

4a2 − 10a + 25

Answer 1

use the discriminant

\[\Delta = b^2 - 4ac\]

when \[\Delta = 0\]

the quadratic is a perfect square

in the first question a = 9, b = -6 and c = 1

then \[\Delta = (-6)^2 - 4 \times9\times1 = 0\]

so a perfect square

Answer 2

that'll work or see if it looks like \(a^2+2ab+b^2\) because that is what you get when you square: \((a+b)^2=a^2+2ab+b^2\)

Answer 3

im soo good at guessing lol