5/13 : 15/52 = 5/13 * 52/15 = 1/13 * 52/3 = 52/39 = 4/3 = 1 1/3
6-(a+4)-(8a-5)-(2x-8)-(6x-4)=6-a-4-8a+5-2x+8-6x+4=6-4+5+8+4-a-8a-2x-6x=19-(-7a)-(-4x)=19+7a+4x
3a+(-9a+4)-5y+(-y-1)=3a+(-9a)+4-5y+(-y)-1=-6a+4-4y-1=6a+3-4y
1,6
обратно число
1/1,6=1/(16/10)=10/16=5/8
Ответ:
1) y=12
2)x=26
Пошаговое объяснение:
1) (76 - 5y)*3 + 56 = 104
(76 - 5y)*3 = 104 - 56
(76 - 5y)*3 = 48
76 - 5y = 48 / 3
76 - 5y = 16
-5y = 16 - 76
-5y = -60
y = 12
2) 20*(24 + x) = 1612 - 612
20*(24 + x) = 1000
24 + x = 1000 / 20
24 + x = 50
x = 50 – 24
x = 26