Answer both for ( brain list , thanks , and a 5 star review)

Kylie explained that (-4x+9)^2 will result in a difference of squares because (-4x+9)^2 (-4x+9)^2 =(-4x)^2+(9)^2=16x^2+81

Adriver from the university of florida women’s swimming and diving team is competing in the in ncaa zone b championships

Can someone factor this fully? my friend and i have two different answers and i would like to know if either of them is right. you in advance. a^2 - b^2 + 25 + 10a