Question

2+bx9-25=40

22-5x(38-4x)=12

11-(7x5-9x9:f:3):8=7

36-42:e:(15:3-4x1)-20=10

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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22 - 5 × ( 38 - 4 x ) = 12

5 × ( 38 - 4 x ) = 22 - 12

38 - 4 x = 10 : 5

4 x = 38 - 2

x = 36 : 4

x = 9

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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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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