Question

2+bx9-25=40
36-42:e:(15:3-4:1)-20=10
11-(7x5-9x9:f:3):8=7
(dx4+20):4=12

Answer 1

Răspuns:

Explicație pas cu pas:

2 + b × 9 - 25 = 40

2 + b × 9 = 40 + 25

2 + b × 9 = 65

b × 9 = 65 - 2

b × 9 = 63

b = 63 : 9

b = 7

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36 - 42 : e : ( 15 : 3 - 4 : 1 ) - 20 = 10

36 - 42 : e : ( 5 - 4 ) = 10 + 20

42 : e : 1 = 36 - 30

42 : e = 6 × 1

e = 42 : 6

e = 7

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Răspuns:  f = 9

Explicație pas cu pas:

11 - ( 7 × 5 - 9 × 9 : f : 3 ) : 8 = 7

( 35 - 81 : f : 3 ) : 8 = 11 - 7

( 35 - 81 : f : 3 ) : 8 = 4

35 - 81 : f : 3 = 4 × 8

81 : f : 3 = 35 - 32

81 : f : 3 = 3

81 : f = 3 × 3

f = 81 : 9

f = 9 → numarul, aflat prin metoda mersului invers

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( d × 4 + 20 ) : 4 = 12

d × 4 + 20 = 12 × 4

d × 4 = 48 - 20

d × 4 = 28

d = 28 : 4

d = 7