Răspuns :
a+b+c=495
1) a=17+b
c=11+a=> c=11+17+b=28+b
17+b+b+28+b=495
45+3b=495
3b=450=> b=450:3=>b=150.
a=167
c=178
3) a,b
a+b=842
b=a+2
a+a+2=842
2a=840=> a=840:2=> a=420
b=a+2=> b=420+2=> b=422
1) a=17+b
c=11+a=> c=11+17+b=28+b
17+b+b+28+b=495
45+3b=495
3b=450=> b=450:3=>b=150.
a=167
c=178
3) a,b
a+b=842
b=a+2
a+a+2=842
2a=840=> a=840:2=> a=420
b=a+2=> b=420+2=> b=422
a+b+c=495
1. a=b+17
c=a+11⇒ c= b+17+11= b+28
b+17+b+b+28=495
3b+45=495
3b=495-45
3b=450
b=450:3=150
a=150+17=167
c=150+28=178
2. a+a+1=441
2a+1=441
2a=441-1=440
a=440:2=220
b=220
3.a+a+2=842
2a+2=842
2a=840
a=840:2=420
b=420+2=422
1. a=b+17
c=a+11⇒ c= b+17+11= b+28
b+17+b+b+28=495
3b+45=495
3b=495-45
3b=450
b=450:3=150
a=150+17=167
c=150+28=178
2. a+a+1=441
2a+1=441
2a=441-1=440
a=440:2=220
b=220
3.a+a+2=842
2a+2=842
2a=840
a=840:2=420
b=420+2=422