20x (x+2) - 20x = x ( x+2)
1) 2x-pi\3=-arctg5+pi*n
x=-1\2*arctg5+pi\6+pi\2*n
2)x\4+pi\6=+-arccos(sqrt3\4)+2pi*n
x=+-4arccos(sqrt3\4)-2pi\3+8pi*n
уравнение
а) 2х-(6х+1)=9
2х-6х-1=9
-4х=10
х=-2,5
б) 4(1-5х)=9-3(6х-5)
4-20х=9-18х+15
-20х+18х=9+15-4
-2х=20
х=-10
в) 1,5(х-6)=1,4(х+5)
1,5х-9=1,4х+7
1,5х-1,4х=7+9
0,1х=16
х=160
1. 3x - 6 = 9
3x = 9+6
3x = 15
x = 5
2. 4x - 2 = 3x - 7
4x - 3x = -7+2
x = -5