Răspuns:
la 17:1+12=13
2+11=13
3+10=13
4+9=13
5+8=13
6+7=13 astea sunt variantele
0+13
13+0
16.
a)
x+y+z=43-11
x+y+z=12
b)
3x+4y+5z=59-27
3x+4y+5z sau 5z+3x+4y=32
c)
x-2y=52-13
x-2y=39
3(x-2y)=117
117+1=118
3x-6y+1=118
17.
13=0+13, 1+12, 2+11, 3+10, 4+9, 5+8, 6+7, 7+6, 8+5, 9+4, 10+3, 11+2, 12+1, 13+0
