I need help with grade 11 math with Pythagorean theorem with a and b

Factor a^3 - 3 + 3a^2 - a. a) (a - 1)(a + 1)(a + 3) b) (a^2 + 1)(a - 3) c) (a^2 - 3)(a + 1)

Ahiker stands at an unknown elevation before he ascends 2 miles up a mountain to an elevation of 9 miles. find the elevation of the hiker before his ascent.

Do you mind if you guys me with this question i’m on number 8