Which equation is correctly solved for y

Write the expression in simplified radical form. show all steps and work including any foil method work. (hint: use the conjugate. no decimal answers.) (9-2√3)/(12+√3)

3-12. write each answer with a reasonable number of figures. find the absolute uncertainty and percent relative uncertainty for each answer. (a) [12.41 (±0.09) + 4.16 (±0.01)] x 7.068 2 (±0.000 4) =? (b) [3.26 (±0.10) x 8.47 (±0.05)] - 0.18 (±0.06) =? (c) 6.843 (±0.008) x 104 + [2.09 (±0.04)- 1.63 (±0.01)] =?

The parabola x = y² - 9 opens: a.)up b.)down c.) right d.)left