Algebra Help (question in description)

Question

A basketball player's hang time is the time spent in the air when shooting a basket. The formula t= sqaure root of d over 2

models hang time, t, in seconds, in terms of the vertical distance of a player's jump, d, in feet. When a particular player dunked a basketball, his hang time for the shot was approximately 1.21 seconds. What was the vertical distance, d, of his jump, rounded to the nearest tenth?

Answer 1

1.21 = square root (d/2)

square both sides to get rid of the square root sign

1.4641 = d/2

multiply both sides by 2

2.9282 = d

rounded to the nearest tenth is 2.9 feet