Respuesta :

first 3 questions are correct.

*remember for a trinomial to be a perfect square
1) first term is a perfect square
2) third term is a perfect square
3) middle term is eight 2 or -2 time the product of the square roots of the 1st and 3rd term
 
last question is incorrect.

(3x - 5)(3x + 5) * notice the different signs

9x² + 15x - 15x - 25
9x² - 25

for Q.1 your choices are correct.

for Q.2 you need to choose, 16^2 + 9 as well (your first choice is correct you just need this one)

for Q.3 your choice is correct.

for Q.4 you also need 9x^2 - 25  (your first choice is incorrect just need this one instead.)