Question

Afla necunoscuta:
a) 100-9×a+5-3×7=38
b) 8:4+9×d-27=39
c) 4×9+8×a+6+7×7=109

Answer 1

Răspuns:

a) 100 - 9a + 5 - 21 = 38

100 - 9a - 16 = 38

-9a + 100 - 16 = 38

-9a + 84 = 38

-9a = 38 - 84

-9a = -46

a = -46/-9

b) 8/4 + 9d - 27 = 39

2 + 9d - 27 = 39

9d - 25 = 39

9d = 39 + 25

9d = 64

d = 64/9

c)36 + 8a + 6 + 49 = 109

8a + 91 = 109

8a = 109 - 91

8a = 18

a = 18/8