Question

(ab+3)(ab-3)-(ab+5)2

Answer 1

(ab+3)(ab-3)-(ab+5)2
a²b² -3ab +3ab -9 -( a²b² +10ab +25)
a²b² -3ab +3ab -9 -a²b² -10ab -25
a²b² -a²b² -3ab +3ab -10ab -9 -25
-10ab -34

Answer 2

 (ab+3)(ab-3)-(ab+5)2

 a^2b^2 - 9 -(a^2b^2 +10ab + 25)

 a^2b^2 - 9 - a^2b^2 -10ab - 25

  - 10ab - 34

  - 2( 5ab + 17)