Question

Найдите корень
1) 3,5-х=8(х+2,8)
2) 3/5(7/9х-1/3)=х-2 1/3

Answer 1

1)
3,5-х=8(х+2,8)
3,5 - х = 8х + 22,4
-х - 8х = 22,4 - 3,5
-9х = 18,9
х = 18,9 : (-9)
х = -2,1

2)
3/5(7/9х-1/3)=х-2 1/3
3/5 • 7х/9 - 3/5 • 1/3 = х - 7/3
7х/15 - 1/5 = х - 7/3
7х/15 - х = -7/3 + 1/5
7х/15 - 15х/15 = -35/15 + 3/15
-8х/15 = -32/15
х = -32/15 : (-8/15)
х = 4