A parabola can be represented by the equation y2 = –x. What are the coordinates of the focus and the equation of the directrix? focus: (negative one-fourth, 0); directrix: x = One-fourth focus: (one-fourth, 0); directrix: x = Negative one-fourth focus: (–4,0); directrix: x = 4 focus: (4,0); directrix: x = –4

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