The equation at the right has been incorrectly solved, the answer to this is b = -7
Replace the CIRCLES by A and the SQUARES by B:
1) A + B = 14 And
2) A - B = 2
Add 1) + 2)
A+B =14
A-B = 2
------ ----
2A+0 = 16 then A = 16/2 = 8. If A = 8, then B = 6
So the CIRCLE = 8 and the SQUARE = 6
4; enlargement !! hope this helps
Fermat's little theorem states that

≡a mod p
If we divide both sides by a, then

≡1 mod p
=>

≡1 mod 17

≡1 mod 17
Rewrite

mod 17 as

mod 17
and apply Fermat's little theorem

mod 17
=>

mod 17
So we conclude that

≡1 mod 17
The answer is 503.39
Hope this helps