а) -4(3a+5)+2a=15-12a - 20 + 2a = 15-10a - 20 = 15-10a = 35a = -3.5
б) 4.5(-2a+4) - a = 8-9a + 18 - a = 8-10a + 18 = 8-10a = -10a = 1
в) -3.4a - (2a + 4) = 23-3.4a - 2a - 4 = 23-5.4a - 4 = 23-5.4a = 27a = -5
г) -8 - 3(a-5) = 9-8 - 3a + 15 = 9-3a + 7 =9-3a = 2a = -2/3
д) 3x - 2(x+4) = 123x - 2x - 8 = 12x - 8 = 12x = 20
е) 5x + 8(x-4) = 75x + 8x - 32 = 713x - 32 = 713x = 39x = 3
а) -4(3a+5)+2a=15
-12a - 20 + 2a = 15
-10a - 20 = 15
-10a = 35
a = -3.5
б) 4.5(-2a+4) - a = 8
-9a + 18 - a = 8
-10a + 18 = 8
-10a = -10
a = 1
в) -3.4a - (2a + 4) = 23
-3.4a - 2a - 4 = 23
-5.4a - 4 = 23
-5.4a = 27
a = -5
г) -8 - 3(a-5) = 9
-8 - 3a + 15 = 9
-3a + 7 =9
-3a = 2
a = -2/3
д) 3x - 2(x+4) = 12
3x - 2x - 8 = 12
x - 8 = 12
x = 20
е) 5x + 8(x-4) = 7
5x + 8x - 32 = 7
13x - 32 = 7
13x = 39
x = 3