How to find the value of $h(99)$ in the function? If $$h(x) + h(x+1) = 2x^2$$ 
and $$h(33) = 99$$
What will be the value of $h(99)$?

From your definition,
$$h(34)=2\times 33^2-h(33)$$
$$h(35)=2\times 34^2-h(34)=2\times 34^2-2\times 33^2+h(33)$$
$$\dots$$
$$h(99)=2\times 98^2 - 2\times 97^2 + 2\times 96^2 -\cdots + 2\times 34^2 - 2\times 33^2 +h(33)\\=2(98^2-97^2+96^2-\cdots+34^2-33^2)+99\\
=2(98+97+\cdots +34+33)+99\\
=8745$$
