Which must be true of a quadratic function whose vertex is the same as its y-intercept?

To finance her community college education, sarah takes out a loan for $2900. after a year sarah decides to pay off the interest, which is 4% of $2900. how much will she pay

Two airplanes start at the same place and travel in opposite directions,one at 395 miles per hour and the other at 422 miles per hour. how many hours will it take for the planes to be 2451 miles apart?

(a.s."similarity in right triangles"solve for xa.) 10b.) 20c.) 14.5d.) [tex] 6\sqrt{3} [/tex]