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Терміново! Розв'яжіть рівняння
1) (x + 3) (x - 5) = - 15
2) дві третіх ікс (x - 3) = одна друга ікс (х + 4)
Ответы 1
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1) (x + 3) (x - 5) = - 15 х²-5х+3х-15= -15х²-5х+3х=0х²-2х=0х(х-2)=0х=0; х=22) 2/3 х(x - 3) = 1/2 х(х + 4) 2/3 х(x - 3)- 1/2 х(х + 4)=0 2/3 х²-2х -1/2 х²-2х=0 *6 4х²-12х-3х²-12х=0 х²-24х=0 х(х-24)=0 х=0; х=24
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Автор:
zaneyo9k - 4 года назад
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