Вложение ................................................
Log(3)21*log(7)3-log(6)3*log(7)6=log(3)21*1/log(3)7-log(6)3*1/log(6)7=
=log(3)21/log(3)7-log(6)3/log(6)7=log(7)21-log(7)3=log(7)3/21=log(7)1/7=-1
((2x+3x)/2)+6=(2x+6)/8
16x+24x+96=4x+12 <Избавились от дробей>
40x-4x=12-96
36x=-84
x=-2-(1/3)
(5x)^3:(5x) = (5x)^2 = 25x^2