Answer:
Remember that a perfect square trinomial can be factored into the form (a+b)^2
or (a-b)^2
Examples:
(x+2)(x+2) is a perfect sq trinomial --> x^2+4x+4
(x-3)(x-3) is a perfect sq trinomial --> x^2-6x+9
(x+2)(x-3) is not a perfect square trinomial because its not in the form (a+b)^2 or (a-b)^2
Now to answer your question,
for the first one, x^2-16x-64, you cannot factor it so it is not a perfect square trinomial
for the second one, 4x^2 + 12x + 9, you can factor that into (2x+3)(2x+3) = (2x+3)^2 so this is a perfect square trinomial
for the third one, x^2+20x+100 can be factored into (x+10)(x+10) so this is also a perfect square trinomial
for the fourth one, x^2+4x+16 cannot be factored so this is not a perfect square trinomial
Therefore, your answer is choices 2 and 3
Read more on Brainly.com - brainly.com/question/10522355#readmore
Step-by-step explanation:
Using pythagorean theorem:
![\begin{gathered} c^2=a^2+b^2 \\ b=\sqrt[]{c^2-a^2} \\ b=\sqrt[]{19^2-17^2} \\ b=\sqrt[]{72} \\ b\approx8.5 \end{gathered}](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%20c%5E2%3Da%5E2%2Bb%5E2%20%5C%5C%20b%3D%5Csqrt%5B%5D%7Bc%5E2-a%5E2%7D%20%5C%5C%20b%3D%5Csqrt%5B%5D%7B19%5E2-17%5E2%7D%20%5C%5C%20b%3D%5Csqrt%5B%5D%7B72%7D%20%5C%5C%20b%5Capprox8.5%20%5Cend%7Bgathered%7D)
The first answer is 25x + 45 = c
The second one is y=3x
Hopes this helps
