Упростите выражение(a-3)(a+3)-(a-5)(a-1) a= -0.5

Question

Упростите выражение(a-3)(a+3)-(a-5)(a-1)
a= -0.5

Comments

-17

Answer 1

... = a^2 - 9 - a^2 + 6a - 5 = 6a - 14 = -3 - 14 = -17

Answer 2

А*а+3а-3а-9-(а*а-а-5а+5)=а*а-9-(а*а-6а+5)=а*а-9-а*а+6а-5=6а-14=6*(-0,5)-14=-3-14=-17