Question

a (2a – 3b) + ( a +b) ( 3b +7a) +9 ( b2 – a2)

Answer 1

7ab +12b square answer hope it will help you

Answer 2

Hola Mate!!

Here's your answer:-

$a(2a - 3b) + (a + b)(3b + 7a) + 9( {b}^{2} - {a}^{2}) \\ = 2 {a}^{2} - 3ab + 3ab + 7 {a}^{2} + 3 {b}^{2} + 7ab + 9 {b}^{2} - 9 {a}^{2} \\ = 2 {a}^{2} + 7 {a}^{2} - 9 {a}^{2} + 3 {b}^{2} + 9 {b}^{2} - 3ab + 3ab + 7ab \\ = 9 {a}^{2} - 9 {a}^{2} + 12 {b}^{2} + 7ab \\ = 12 {b}^{2} + 7ab$

Hope it helps
Mark me as brainliest if it's correct