Question

If a tightrope walker falls, he will land on a safety net. His height h in feet after a fall can be modeled by h(t) = 60 - 16t2, where t is the time in seconds. If the safety net is 11 feet above the ground, how many seconds will the tightrope walker fall before landing on the safety net? Round your answer to the nearest hundredth. _____ s

Answer 1

hint:

60 - 16t^2 = 11

solve for t

does that help?

Answer 2

Do you subtract like 60 or 11 from both sides?

Answer 3

yes. you subtract 60 from both sides

Answer 4

-16^2=-49 right? and then would you square both sides?

Answer 5

-16t^2=-49

Answer 6

no...you divide both sides by -16

Answer 7

so t^2=3.0625?

Answer 8

don't use a calculator

Answer 9

put them in fraction form

Answer 10

-16/16t^2=-49/16?

Answer 11

divide by -16...not just 16

Answer 12

the first part would be 1 though right?

Answer 13

right. what about the right side?

Answer 14

3 1/16?

Answer 15

actually it's 49/16

\[\implies t^2 = \frac{49}{16}\]
make sense?

Answer 16

yeah

Answer 17

now take the square root of both sides

Answer 18

t= 7/4?

Answer 19

right

Answer 20

now put that in decimal form

Answer 21

t=1.75

Answer 22

right.

Answer 23

so your answer is 1.75 seconds

Answer 24

thank you, for your help

Answer 25

welcome