What is the simplest form of the expression square root 3 - square root 6/square root 3 + square root 6? Answer fast please

Maria walks a round trip of 0.75 mile to school every day.how many miles will she walk in 4.5 days

I'm confused on this could anyone me and show me what i need to do to solve it.

Given: lines a and b are parallel and line c is a transversal. prove: 2 is supplementary to 8 what is the missing reason in the proof? statement reason 1. a || b, is a transv 1. given 2. ∠6 ≅ ∠2 2. ? 3. m∠6 = m∠2 3. def. of congruent 4. ∠6 is supp. to ∠8 4. def. of linear pair 5. ∠2 is supp. to ∠8 5. congruent supplements theorem corresponding angles theorem alternate interior angles theorem vertical angles theorem alternate exterior angles theorem