Let $a$ and $b$ be the roots of this equation:

$$x^2 - x - 5 = 0$$

Find the value of

$$(a^2 + 4b - 1)(b^2 + 4a - 1)$$

Without calculating the values of a and b.

I saw this on a problems site and tried it but I got `100` and I don't think that's correct.