Предмет: Алгебра, автор: stepanspiridon

(9x-4)^2-(7x+5)^2?если x=1,5

Ответы

Автор ответа: linajk

формула:(а-б)×2=а×2+2аб+б×2
81 $x^{2}$ +72х+16-49 $x^{2}$ -70х-25
32 $x^{2}$ +2х-9
32×2.25+3-9=66

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