Question

1) 5x = 7,25;


2) –12x = 0,96;


3) 0,7x – 8 = 20;


4) 3 · (x – 5,4) = 18;


5) 35 = 7(–4x + 3x);


6) 0,5x – 8 = 20;7) –5,4 – 2x = –4,6;


8) 7x + 2,1 = –4,9;


9) 12 – 4x + 16 = 28;


10) –6,2x – 12 – 2,8x = 6;


11) –3(0,5x – 25) = 0;


12) 3(2x + 13) – 6x = 0.
Допоможіть

Answer 1

1)

x = 7.25/5 = 1.45

x = 1.45

2)

x = 0.96/-12 = -0.08

x = -0.08

3)

x = (20+8)/0.7 = 40

x = 40

4)

x = (18+5.4)/3 = 9.4

x = 9.4

5)

x = 35/7 = 5

x = 5

6)

x = (20+8)/0.5 = 56

x = 56

7)

x = (-4.6+5.4)/(-2) = 0.9

x = 0.9

8)

x = (-4.9-2.1)/7 = -1

x = -1

9)

x = (12+16-28)/(-4) = 1

x = 1

10)

x = (6-12)/(-9) = -2

x = -2

11)

x = (75-0)/(-1.5) = 50

x = 50

12)

x = (0-39)/(6) = -13

x = -13

Answer 2

1. 5x = 7,25;
x = 7,25/5
x = 1,45
2. –12x = 0,96;
x = 0,96/(-12)
x = -0,08
3. 0,7x – 8 = 20;
0,7x = 20 + 8
0,7x = 28
x = 28/0,7
x = 40
4. 3 · (x – 5,4) = 18;
3x - 16,2 = 18
3x = 18 + 16,2
3x = 34,2
x = 34,2/3
x = 11,4
5. 35 = 7(–4x + 3x);
35 = 7(-1x)
-7 = -x
x = 7
6. 0,5x – 8 = 20;
0,5x = 20 + 8
0,5x = 28
x = 28/0,5
x = 56
7. –5,4 – 2x = –4,6;
-2x = -4,6 + 5,4
-2x = 0,8
x = 0,8/(-2)
x = -0,4
8. 7x + 2,1 = –4,9;
7x = -4,9 - 2,1
7x = -7
x = -1
9. 12 – 4x + 16 = 28;
-4x = 28 - 12 - 16
-4x = 0
x = 0
10. –6,2x – 12 – 2,8x = 6;
-9x = 18
x = -2
11. –3(0,5x – 25) = 0;
-1.5x + 75 = 0
-1.5x = -75
x = 50
12. 3(2x + 13) – 6x = 0;
6x + 39 - 6x = 0
39 = 0