- 1/5 + 8/15= -3/15+8/15=5/15=1/3
-3 1/3 -1 1/6= -10/3-7/6= -20/6-7/6= -27/6= -9/2=
= -4 1/2
-4 1/6 : (-2 1/12)= -25/6: (-25/12)=25/6 * 12/25=
=2
5/6 * (-3/10) -4/5 : 1 1/15=
5/6 * (-3/10)= -3/10 * 5/6=1/4
4/5 : 1 1/15=4/5 : 16/15=4/5 * 15/16=3/4
1/4-3/4= -2/4= -1/2
(-4/5)² * 1 9/16 *(-2)=16/25 * 25/16 *(-2)= -2
-6х=18х-72
-6х-18х= -72
-24х= -72
х=3
Ответ:3
30(12х-40)=12-4х
360х-1200=12-4х
364х=1212
х= 3 30/91