3x²-0.12=0
x²=0.04
x=±0.2
0.8x-28-1.5x-30=5
-0.7x=63
x=63/-0.7
x=-90
3х - 1 = 5 - 2х
3х + 2х = 5 + 1
5х = 6
х = 6/5
х = 1,2