Question

10. Află numerele necunoscute: 6 Sesa a + 7 = 12 a + 9 = 21 c+ c = 12 unido 15 + c = 30 b - 13 = 17 b- 5 = 18 30 - C = 19 12 - c= 3​

Answer 1

Răspuns:

a + 7 = 12

a = 12 - 7

a = 5

a + 9 = 21

a = 21 - 9

a = 12

c + c = 12

2c = 12

c = 12 : 2

c = 6

15 + c = 30

c = 30 - 15

c = 15

b - 13 = 17

b = 17 + 13

b = 30

b - 5 = 18

b = 18 + 5

b = 23

30 - C = 19

c = 30 - 19

c = 11

12 - c = 3​

c = 12 - 3

c = 9

Answer 2

a + 7 = 12 => a = 12 - 7 => a = 5

a + 9 = 21 => a = 21 - 9 => a = 12

c + c = 12 => 2c = 12 => c = 12 : 2 => c = 6

15 + c = 30 => c = 30 - 15 => c = 15

b - 13 = 17 => b = 17 + 13 => b = 30

b - 5 = 18 => b = 18 + 5 => b = 23

30 - C = 19 => 30 = 19 + c => c = 30 - 19 => c = 11

12 - c = 3 => 12 = 3 + c => c = 12 - 3 => c = 9