Question

Afla numerele necunoscute:
a) 64+(6×a-32)=80
b)91=(45+b):9+9×9

Answer 1

Răspuns:

Explicație pas cu pas:

a)

64 + ( 6 × a - 32 ) = 80

6 × a - 32 = 80 - 64

6 × a - 32 = 16

6 × a = 16 + 32

a = 48 : 6

a = 8

________________

b)

91 = ( 45 + b ) : 9 + 9 × 9

91 = ( 45 + b ) : 9 + 81

91 - 81 = ( 45 + b ) : 9

10 = (45 + b ) : 9

45 + b = 9 × 10

45 + b = 90

b = 90 - 45

b = 45

Answer 2

a) 64 + ( 6 × a - 32 ) = 80

64 + 6 × a - 32 = 80

32 + 6 × a = 80

6 × a = 80 - 32

6 × a = 48

a = 48 : 6

a = 8

b) 91 = ( 45 + b ) : 9 + 9 × 9

91 = ( 45 + b ) : 9 + 81

91 - 81 = ( 45 + b ) : 9

10 = ( 45 + b ) : 9

45 + b = 10 × 9

b = 90 - 45

b = 45