0.4z-5/7z=4.4 помогите

Question

0.4z-5/7z=4.4 помогите

Answer 1

Z(4/10 -5/7) = 4.4
z * (2/5 - 5/7) = 4.4
z( - 11/35) = 4 2/5
-z *11/35 = 22/5
z = - 22/5 : 11/35
z = - 22/5 *35/11
z = - 14