Question

Va rog ajutati-ma!

1) Se stie ca: ab+ac+a=165 si b+c=10. aflati a.
2) Se stie ca a+2b+c=51 si 2a+b+2c=42. Aflati a+b+c

Answer 1

a(b+c+1)=165
a(10+1)=165
a=165:11
a=15

a+2b+c=51
a+c=51-2b
2(a+c)+b=42
2(51-2b)+b=42
102-4b+b=42
3b=102-42
b=20
a+c=51-2b=51-40=11
a+b+c=20+11=31

Answer 2

1) a(b+c+1)=165
a(10+1)=165
11a=165
a=15
2)a+2a+b+2b+c+2c=51+42
3a+3b+3c=93
a+b+c=31