Question

Gíup tui với

Answer 1

`#3107.101107`

`7)`

`G = (5a - 3)(3b - 5) - (3a - 5)(5b - 3)`

`= 5a(3b - 5) - 3(3b - 5) - [ 3a(5b - 3) - 5(5b - 3)]`

`= 15ab - 25a - 9b + 15 - (15ab - 9a - 25b + 15)`

`= 15ab - 25a - 9b + 15 - 15ab + 9a + 25b - 15`

`= -25a - 9b + 9a + 25b`

`= -16a + 16b`

`= 16(b - a)`

Vì `16 \vdots 16`

`=> 16(b - a) \vdots 16`

`=> G \vdots 16 (đpcm).`

Answer 2

\(G=15ab-25a-9b+15-15ab+9a+25b-15\)

\(=-16a+16b=-16\left(a-b\right)⋮16\)