Question

уравнение (7×x-140)÷5=78

Answer 1

7х-140=78*5
7х=390+140
х=75,71

Answer 2

7x-140=78*5
7x=78*5+140
x=(78*5+140)÷7
x=530÷7
x=75 5/7

Answer 3

спас