or
or
x - 3
= 12 - 3
= 9
(x - 7)(x - 9)
=(12 - 7)(12 - 9)
=5 × 3
=15
(x - 5)(x - 3)
=(12 - 5)(12 - 3)
=7 × 9
=63 (answer:)
(x - 8)(x - 7)
=(12 - 8)(12 - 7)
=4 × 5
=20
x - 2
=12 - 2
=10
