Which is the directrix of a parabola with equation x2 = 4y?

Write the equations in logarithmic form 10^3=1,000

Cody ran nine miles on his first day of training. the next day he ran 1/8 that distance. how far did he run the second day?

Use mathematical induction to prove the statement is true for all positive integers n, or show why it is false. 1^2 + 4^2 + 7^2 + + (3n - 2)^2 = [n(6n^2-3n-1)/2]