Răspuns:
Explicație pas cu pas:
b) (23 - x ) : 6 = 3
23 - x = 3 · 6
23 - x = 18
x = 23 - 18
x = 5
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c) 5 · ( 3·x - 9 ) = 60
3·x - 9 = 60 : 5
3·x = 12 + 9
3 · x = 21
x = 21 : 3
x = 7
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d) ( 23 - 5·x ) : 9 = 2
23 - 5 · x = 2 × 9
23 - 5 · x = 18
5 · x = 23 - 18
5 · x = 5
x = 5 : 5
x = 1
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e) 24 : ( 5 - x ) = 6
5 - x = 24 : 6
5 - x = 4
x = 5 - 4
x = 1
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f) 32 : ( 13 - 5 · x ) = 4
13 - 5 · x = 32 : 4
13 - 5 · x = 8
5 · x = 13 - 8
x = 5 : 5
x = 1
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g) 3 · x - 15 : 3 = 19 + 3
3 · x - 5 = 22
3 · x = 22 + 5
3 · x = 27
x = 27 : 3
x = 9
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h) 5 · x - 21 : 7 = 4 + 13
5 · x - 3 = 17
5 · x = 17 + 3
5 · x = 20
x = 20 : 5
x = 4
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i) 13 - 14 : x = 18 - 7
13 - 14 : x = 11
14 : x = 13 - 11
14 : x = 2
x = 14 : 2
x = 7
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3.
a) x + 5 · ( 33 + 128 ) = 895
x + 5 · 161 = 895
x + 805 = 895
x = 895 - 805
x = 90
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b) x - 53 · ( 49 - 3 · 12) = 996
x - 53 · ( 49 - 36 ) = 996
x - 53 · 13 = 996
x - 689 = 996
x = 996 + 689
x = 1 685
