# What is the missing number, can anyone solve this? My original puzzle

What is the missing number that should be put in place of the question mark?

3,3=17

2,5=28

3,4=24

4,5=40

5,8=88

6,11=156

6,9=?

116

The pattern/reasoning is

(a^2 + b^2) -1 = answer

• No brackets needed. – curiousdannii Sep 13 at 6:44
• Good point. Clearly it's been a while since I worked on orders of operations. Guess it's just a little window into how I was thinking about the answer. – MobileGlick Sep 13 at 16:00

If the three numbers in each "equation" are $$a$$, $$b$$, $$c$$ then one possible solution is

$$Min(a, 5)^2 + b^2 - 1 = c$$, giving the answer $$c = 105$$ for the last.

Edit

For good measure, the corrected version of the puzzle has the simpler solution

$$a^2 + b^2 - 1 = c$$, giving the answer $$c = 116$$ for the last.

• It doesnt work for 6,11 but fits all others. Maybe there was a typo? – Belhenix Sep 12 at 23:18
• It works. But I wonder if "6,11 = 146" was meant to be "6,11 = 156" which would remove the need for the whole "Min" part of it which seems a bit arbitrary? – JS1 Sep 12 at 23:18
• yes you were right there was an error in the puzzle – Deepthinker101 Sep 13 at 1:37