Question

1. Află-l pe a din egalitatea:
11 + [ 17 - (a x 9 + 2): 100 ]: 3 x 18 + 20 = 11 x 11.​

Answer 1

Răspuns:

11 + [ 17 - (a x 9 + 2): 100 ]: 3 x 18 + 20 = 11 x 11

11+[17-(a·9+2):100]:3·18+20=121

[17-(a·9+2):100]:3·18=121-11-20

[17-(a·9+2):100]:3·18=90

[17-(a·9+2):100]:3=90:18

[17-(a·9+2):100]:3=5

[17-(a·9+2):100]=5·3

17-(a·9+2):100=15

(a·9+2):100=17-15

a·9+2=2·100

9a=200-2

9a=198

a=198:9

a=22