Пошаговое объяснение:
1)
2(х-6)=3(х+7)
2x - 12 = 3x + 21
3x - 2x = -12 - 21
x = -33
2)
-5(3+2х)=(х-2)9
-15 - 10x = 9x - 18
9x + 10x = 18 - 15
19x = 3
x = 3/19
3)
(4х-3)6=-3(10+6х)
24x - 18 = -30 - 18x
24x + 18x = -30 + 18
42x = -12
x = -12 : 42
x = -2/7
4)
30(8х-10)=6(х-5)
240x - 300 = 6x - 30
240x - 6x = 300 - 30
234x = 270
x = 270 : 234
x = 1 2/13
5)
12(-7-3х)=2(-5х+9)
-84 - 36x = -10x + 18
36x - 10x = -84 - 18
26x = -102
x = -102 : 26
x = -3 12/13
6)
3(5х-15)=(2х+3)4
15x - 45 = 8x + 12
15x - 8x = 12 + 45
7x = 57
x = 57 : 7
x = 8 1/7
7)
(25-15х)2 =-7(5+2х)
50 - 30x = -35 - 14x
30x - 14x = 50 + 35
16x = 85
x = 85 : 16
x = 5 5/16
8)
-5х-12=3(-4+3х)
-5x - 12 = -12 + 9x
9x + 5x = 12 - 12
14x = 0
x = 0
9)
2х=70-5х
2x + 5x = 70
7x = 70
x = 70 : 7
x = 10
10)
-4(-19+23х)=(-21х-2)16
76 - 92x = -336x - 32
336x - 92x = -32 - 76
244x = -108
x = -108 : 244
x = -27/61
Пошаговое объяснение:
(6-2,35)×1,4=5,11
1) 6-2,35=3,65
2) 3,65×1,4=5,11
8×5,8-0,4×2,3=45,48
8×5,8=46,4
0,4×2,3= 0,92
46,4-0,92=45,48
156-2,4×0,15= 155,64
1) 2,4×0,15=0,36
2) 156-0,36= 155,64
1,6×9,75+9,75×8,4=
1) 1,6×9,75= 15,6
2) 9,75×8,4= 81,9
15,6+81,9= 97,5
0,7×100-3,5×10-0,036×100=31,4
1)0,7×100=70
2) 3,5×10=35
3) 0,036×100=3,6
4) 70-35=35
5)35-3,6= 31,4
Х-2,94=5
Х=5+2,94
Х=7,94
7,94-2,94=5
5=5
16-х=5,34
Х=16-5,34
Х= 10,66
16-10,66=5,34
5,34=5,34
Х-1,35=6
Х=6+1,35
Х=7,35
7,35-1,35=6
6=6
(Х-11,8)+5,7=11,2
Х-11,8=11,2-5,7
Х-11,8= 5,5
Х= 5,5+11,8
Х= 17,3
(17,3-11,8)+5,7=11,2
11,2=11,2
а=6,8см
Р=?
S=?
P■=4×a
S=a×b
P= 4×6,8см=27,2см
S= 6,8×6,8= 46,24см2
a= 10,6cм
b=?, на 2 см больше__\
Р= ?
S= ?
b = 10,6+2=12,6cм
P= (a+b)×2
S= a×b
P= (10,6+12,6)×2=46,4 см
S= 10,6×12,6= 133,56cм4
