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2013-10-17T19:17:10+02:00
A . 23+16x = 31
16x=31-23
16x=8
x=8/16
x=1/2

b. 3x - 14 = 9
3x=9+14
3x=23
x=23/3

c. 2,5x + 5,6 = 12
2,5x=12-5.6
2.5x=6.4
x=6.4/2.5
x=2.56

d. 5x +1 = 2x +19
5x-2x=19-1
3x=18
x=18/3
x=6

e. 8x +3 = x + 15
8x-x=15-3
7x=12
x=12/7

f. 7,8i - 8 = 1,3i +2
7.8i-1.3i=2+8
6.5i=10
i=10/6.5

2013-10-17T19:17:25+02:00
A . 23+16x = 31
16x = 31 - 23
16x = 8
x = 8/16

b. 3x - 14 = 9
3x = 9 + 14
3x = 23
x = 23/3

c. 2,5x + 5,6 = 12
2,5x = 12 - 5,6
2,5x = 6,4
x = 6,4/2,5

d. 5x +1 = 2x +19
5x - 2x = 19 - 1
3x = 18
x = 18/3

e. 8x +3 = x + 15
8x - x = 15 - 3
7x = 12
x = 12/7

f. 7,8i - 8 = 1,3i +2
7,8i - 1,3i = 2 + 8
6,5i = 10
i = 10/6,5