Question

-5(2.8х-1.2)+0.2(7-40х) при х=-3.5

Answer 1

-5(2.8х-1.2)+0.2(7-40х) =-14x+6+1,4-8x=-22x+7,4

x=-3,5 =>-22*(-3,5)+7,4=84,4.

Answer 2

-5(2.8х-1.2)+0.2(7-40х) при х=-3.5

-5(2.8х-1.2)+0.2(7-40х)=-14х+6+1,4-8х=-22х+7,4

при х=-3.5

-22х+7,4=-22*(-3,5)+7,4=77+7,4=84,4

Ответ:84,4