Question

решите уравние! плзззззззз

Answer 1

а - 3/7а = 2,8
4/7а = 2 4/5
а = 2 4/5 : 4/7
а = 4 9/10 = 4,9

Answer 2

$1a- \frac{3a}{7} =2,8$

$\frac{7a}{7} - \frac{3a}{7}=2,8$

$\frac{4a}{7} =2,8$

$4a=2,8*7 a=2,8*7/4=7*0,7=4,9$