Verified answer

its just a perfect square

a^2 +2ab+b^2

so 81a^2+144ab+64b^2 is the answer

(9a + 8b)^2

(9a + 8b)(9a + 8b) =

81a^2 + 72ab + 72ab + 64b^2 =

81a^2 + 144ab + 64b^2.

(9a + 8b)(9a + 8b)

81a^2 + 72ab + 72ab + 64b^2

81a^2 + 144ab + 64b^2

Have a good day!

81a^2+64b^2+144ab