Question

138+320c-125c-71c=30-20+8c-100


16x-31+×=40-30×-71

24x-31x+16=18-9x

7x+12x-13+×=20×-23+10×+10

-1=5+11×-10+21×

×+1+(2×+2)=×+(×+6)+2

18+6×-(2+3x)=×-8+6 (×+2)

×+1+(2×+2)=×(×+6)+2

18+6×-(2+3×)=×-8+6 (×+2)

×+1-(2×+2)=×-(×+6)+2

Answer 1

138+320c-125c-71c=30-20+8c-100
320c - 125c - 71c + 138 = 30 - 20 + 8c - 100
320c - 196c + 138 = - 90 + 8c
124c + 138 = 8c - 90
124c - 8c = - 90 - 138
116c = - 228
c = - 228/116
c = - 57/29

COMPROBAMOS LA SOLUCIÓN.
138+320c-125c-71c=30-20+8c-100
138 + 320 (- 57/29) - 125 (- 57/29) - 71 (- 57/29) = 30 - 20 + 8 (- 57/29) - 100
138 - 18240/29 + 7125/29 + 4047/29 = - 90 - 456/29
(- 18240 + 7125 + 4047)/29 + 138 = (- 90 * 29 - 456)/29
- 3066/29 = - 3066/29
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16x-31+×=40-30×-71
16x - 31 + x = 40 - 30x - 71
17x - 31 = - 31 - 30x
17x + 30x = - 31 + 31
47x = 0
x = 0/47
x = 0

COMPROBAMOS LA SOLUCIÓN.
16x - 31 + x = 40 - 30x - 71
16 (0) - 31 + 0 = 40 - 30 (0) - 71
0 - 31 + 0 = 40 - 0 - 71
- 31 = - 31
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24x-31x+16=18-9x
- 7x + 16 = 18 - 9x
- 7x + 9x = 18 - 16
2x = 2
x = 2/2
x = 1

COMPROBAMOS LA SOLUCIÓN.
24x-31x+16=18-9x
24 (1) - 31 (1) + 16 = 18 - 9 (1)
24 - 31 + 16 = 18 - 9
9 = 9
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7x+12x-13+×=20×-23+10×+10
7x + 12x - 13 + x = 20x - 23 + 10x + 10
7x + 12x + x - 13 = 20x + 10x - 23 + 10
20x - 13 = 30x - 13
20x - 30x = - 13 + 13
- 10x = 0
x = 0/-10
x = 0

COMPROBAMOS LA SOLUCIÓN.
7x + 12x + x - 13 = 20x + 10x - 23 + 10
7 (0) + 12 (0) + 0 - 13 = 20 (0) + 10 (0) - 23 + 10
0 + 0 + 0 - 13 = 0 + 0 - 23 + 10
- 13 = - 13
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-1=5+11×-10+21×
- 1 = 5 + 11x - 10 + 21x
- 1 = 5 - 10 + 11x + 21x
- 1 = - 5 + 32x
- 1 + 5 = 32x
4 = 32x
4/32 = x
1/8 = x
x = 1/8

COMPROBAMOS LA SOLUCIÓN.
- 1 = 5 + 11x - 10 + 21x
- 1 = 5 + 11 (1/8) - 10 + 21 (1/8)
 -1 = 5 + 11/8 - 10 + 21/8
- 1 = (11 + 21)/8 + 5 - 10
- 1 = (32)/8 - 5
- 1 = 4 - 5
- 1 = - 1
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×+1+(2×+2)=×+(×+6)+2
x + 1 + (2x + 2) = x + (x + 6) + 2
x + 1 + 2x + 2 = x + x + 6 + 2
3x + 3 = 2x + 8
3x - 2x = 8 - 3
x = 5


COMPROBAMOS LA SOLUCIÓN.
x + 1 + (2x + 2) = x + (x + 6) + 2
5 + 1 + (2 * 5 + 2) = 5 + (5 + 6) + 2
5 + 1 + (10 + 2) = 5 + (11) + 2
6 + (12) = 5 + 11 + 2
18 = 18
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18+6×-(2+3x)=×-8+6 (×+2) 
18 + 6x - (2 + 3x) = x - 8 + 6 (x + 2)
18 + 6x - 2 - 3x = x - 8 + 6x + 12
16 + 3x = 7x + 4
3x - 7x = 4 - 16
- 4x = - 12
x = - 12/-4
x = 3

COMPROBAMOS LA SOLUCIÓN.
18 + 6x - (2 + 3x) = x - 8 + 6 (x + 2)
18 + 6 (3) - (2 + 3 * 3) = 3 - 8 + 6 (3 + 2)
18 + 18 - (2 + 9) = - 5 + 6 (5)
36 - (11) = - 5 + 30
36 - 11 = 25
25 = 25
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×+1-(2×+2)=×-(×+6)+2
x + 1 - (2x + 2) = x - (x + 6) + 2
x + 1 - 2x - 2 = x - x - 6 + 2
- x - 1 = - 4
- x = - 4 + 1
- x = - 3
x = 3

COMPROBAMOS LA SOLUCIÓN.
x + 1 - (2x + 2) = x - (x + 6) + 2
3 + 1 - (2 * 3 + 2) = 2 - (2 + 6) + 2
3 + 1 - (6 + 2) = 2 - (8) + 2
4 - (8) = 2 - 8 + 2
4 - 8 = 4 - 8
- 4 = - 4
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Listo, ya está todo, hay dos que se repiten por eso solo hice una vez.