$s(t)=-16t^2+21t+3$ and we are looking for the times when the position of the ball is 9 feet. That means that we simply plug in a 9 for s(t) and factor to solve for t:

$9=-16t^2+2t+3$ and

$0=-16t^2+21t-6$ and this is what we factor to find t:

t = .42 sec and then again on its way back down at t = .89 sec

5 0

3 years ago

As part of their fundraising for Right To Play, the student council is having a fun-fair at lunch in the school yard. You will b

Lubov Fominskaja [6]

Step-by-step explanation:

I used a co-ordinate graph and place the ticket booth at the origin then I chose difference of four but you can choose any and place three events equidistant from the origin by using the X- and Y- axis to easily determined a distance of 4 from the origin .

(0-4, 0) =( 4,0)

(0+4, 0) = (4 ,0)

(0, 0+4) = (0, 4)

if the both are placed first u would need to find the equation of a circle that contains all three points and place the booth at centre

you do this by creating the system of 3 equations inputting the x,y coordinates of each booth and solving for h,k,r

equation of a circle (X-H) 2 +( Y-K) 2 = r2

Hope It helps

:DD have a nice day

6 0

3 years ago