Предмет: Математика, автор: rob6

Решите уравнение
x^2-4x=21

Ответы

Автор ответа: nafanya2014

0

x²-4x-21=0
D=(-4)²-4·1·(-21)=16+84=100=10²
x₁=(4-10)/2=-3 или х₂=(4+10)/2=7
О т в е т. -3; 7

Автор ответа: ШереметИрина

0

максимально подробно)))))))))))))))))))))))))))))

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