I need help on this!!

An arrow is shot vertically upward at a rate of 180ft/s. use the projectile formula h=−16t2+v0t to determine at what time(s), in seconds, the arrow is at a height of 420ft. round your answer(s) to the nearest tenth of a second.

What statement is true? 2x^2-9x+2=-1

Witch represents the inverse of the function f(x)=1/4x-12