Harrison plays a game in which he uses a net to catch balls that are randomly launched from holes in the ground. the height of one ball after t seconds is represented by the function f(t) = –16t2 + 20t. after how many seconds does the ball return to the ground? round to the hundredths place as needed. edit: answer is 1.25

⇒ t = 1.25 seconds  

Step-by-step explanation:

The height of one ball after t seconds is represented by the function f(t) = -16·t² + 20·t

We need to find : After how many seconds does the ball return to the ground

Solution :

When the ball will return to the ground the height of the ball will be 0

⇒ f(t) = 0

So, finding the value of t when f(t) = 0

⇒ -16·t² + 20·t = 0

⇒ t·( -16 t + 20 ) = 0

⇒ t = 0 or ( -16 t + 20 ) = 0

t = 0 is rejected because initially the ball is not on the ground.

⇒ ( -16 t + 20 ) = 0

⇒ - 16t = -20

⇒ 16t = 20

⇒ t = 1.25 seconds

step-by-step explanation:

y = | -2(-2) |     →     y = | 4 |     →     y = 4       ⇒   (-2, 4)

y = | -2(-1) |     →     y = | 2 |     →       y =   2       ⇒   (-1, 2)    

y = | -2(0) |     →     y = | 0 |     →       y = 0         ⇒   (0, 0)

y = | -2(1) |   c →     y = | -2 |     →     y =   2         ⇒   (1, 2)    

y = | -2(2) |     →     y = | - 4 |     →     y =   4         ⇒   (2, 4)