Question

Află numerele necunoscute:

7X3 - x = 14
8X x + 9 = 49
2X9+x=61
x+4-8 = 12

Answer 1

7·3 - x = 14
21-x=14
x=21-14
x=7

8· x + 9 = 49
8x=49-9
8x=40
x=40:8
x=5


2·9+x=61
18+x=61
x=61-18
x=43

x+4-8 = 12
x=12-4+8
x=8+8
x=16

Answer 2

21 - x = 14 ⇒  x = 7
8x + 9 = 49 ⇒ 8x = 40 ⇒ x = 40 : 8 ⇒ x = 5
18 + x = 61 ⇒ x= 61 - 18 ⇒ x = 43
x + 4 - 8 = 12 ⇒ x - 4 = 12 ⇒ x = 16