Предмет: Алгебра, автор: Aventgame

Помогите пожалуйста!!!

Приложения:

Ответы

Автор ответа: erzhan9210

0

1ый способ
х²+8х+12=(х+2)(х-а)
(х+2)(х-а)=х²+2х-ах-2а=х²+(2-а)х-2а
2-а=8
а=2-8=-6
-2а=12
а=-6
ответ а=-6

2ой способ
х²+8х+12
Д=8²-4*12=64-48=16=4²
х=(-8±4)/2
х1=-4/2=-2
х2=-12/2=-6
а=-6

Автор ответа: Checov7400

0

х²+8х+12=(х+2)(х-а)
х²+2*х*4+16-4=(х+4)²-4=(х+4-2)(х+4+2)=(х+2)(х+6)
(х+2)(х+6)=(х+2)(х-а)
х+6=х-а
а=х-х-6
а=-6
Ответ: а=-6

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