Chapter 10.2, Problem 10AYU

To determine

To fill: If $a=4,$ then the equation of the directrix is $\underset{\_}{}.$

Answer to Problem 10AYU

  $\underset{\_}{y=-2}.$

Explanation of Solution

Given:

If $a=4,$ then the equation of the directrix is $\underset{\_}{y=-2}.$

The directrix of parabola is $y=k-p=2-4=-2$