SinA=a/c
sinA=15/c
c²=a²+b²=20²+15²=625
c=25
sinA=15/25=0.6
(24960:(300(200—6х):115))=8
300(200-6x):115 = 24960 : 8
300(200-6x):115=3120
300(200-6x)=3120*115
300(200-6x)=358800
200-6x=358800:300
200-6x=1196
6x=200-1196
6x=-996
x=-996:6
x = -166
2r =4 ( 2 *2 ) 6 ( 2 *3) 8 ( 2 * 4 ) / 5r 10 15 20 / 7 21 42 63 я думаю ты понел
244006 I58
232 I4207
120
116
406
406
0
2 9/26 + 3 7/39 - 4 7/13 = 2 27/78 + 3 14/78 - 4 42/78 = (2 + 3 - 4) + (27/78 + 14/78 -42/78) = 1 + (- 1/78)= 1 - 1/78 = 77/78