А) 0.3(5x–7)=3(0.2x+3.2)
1.5x–2.1=0.6x+9.6
0.9x=11.7
x=13
б) 4(1.2x+3.7)–2.8=5.2x
4.8x+14.8–2.8=5.2x
0.4x=12
x=30
в) (4(1/6)y+11(1/4))(4/15)=(2/3)y+5(2/3)
(100/90)y+(180/60)=(2/3)y+5(2/3)
(10/9)y–(6/9)y=(17/3)–(9/3)
(4/9)y=(8/3)
(4/9)y=(24/9)
y=(4/9)*(9/24)
y=(1/6)