After t seconds, a ball tossed in the air from the ground level reaches a height of h feet given by the equation h = 144t-16t^2What is the height of the ball after 3 seconds?

What is the maximum height the ball will reach?

Find the number of seconds the ball is in the air when it reaches a height of 224 feet.

After how many seconds will the ball hit the ground before rebound?

Answers

Answer 1
Answer: 144t-16t^2= 16t(9-t)
after 3 seconds (just substitute t=3):
16(3)(9-3)=
16(3)(6)=
16*18=
288
maximum height: find the average of the roots:
the roots of 16t(9-t) are t=0 or t=9
since it's a parabola, the maximum is at t=4.5, at 324 ft
if its height is 224 feet, the equation is 224=144t-16t^2
16t^2-144t+224=0
divide by 16: t^2-9t+14=0
this can be factored as (t-2)(t-7)=0
the roots are t=2 and t=7, so the ball has been in the air for either 2 seconds or 7 seconds
the roots to 144t-16t^2 are 0 and 9, so the ball will hit the ground 9 seconds after being thrown
Answer 2
Answer: h = -16t^2 + 144t
when you substitute a number in for t, it will tell you how high in the air the ball is after that many seconds. to find the height at three seconds, put in 3 for t.
h = -16*9 + 144*3
h = -144 + 3*144
h = 2*144 (i didn't want to multiply out 3*144 cause im lazy, so i combined like terms as if 144 was a variable.)
h = 288
after 3 seconds, the ball is 288ft in the air.

the maximum height is more complicated (and feel free to skip this paragraph if you think it'll confuse you more.) you could do it with a graphing calculator by graphing the function f(x)=-16x^2+144t and using a maximum feature. you could also use differential calculus to find it. but i think the best way is the way suggested by the person who answered before me, that is, finding the average of the roots. since the parabola's line of symmetry is perpendicular to the x-axis, that means the places the parabola intersects the x-axis (the roots) will be the same distance from the axis of symmetry and therefore the same distance from the vertex (the maximum point of the parabola.)

the roots of the parabola can be found this way:
h = -16t^2 + 144t
0 =  -16t^2 + 144t
0 = t(-16t + 144)
0 = t or 0 = -16t + 144
16t = 144
t = 9
the roots are t=0 and t=9, therefore the line of symmetry (the middle of the parabola) is t=4.5. to find the maximum point of the parabola, plug 4.5 into the function for t and find the resulting height.
h = -16(4.5)^2 + 144(4.5)
h =  -324 + 648
h = 324
so the maximum height happens at t=4.5 seconds, and the maximum height is 324ft.

to find how long it takes for the ball to be at 224 feet in the air, substitute 224 in for h:
h = -16t^2 + 144t
224 = -16t^2 + 144t
56 = -4t^2 + 36t divide by 4
14 = -t^2 + 9t divide by 4 again
t^2 - 9t + 14 = 0 rearrange
(t - 7)(t - 2) = 0
t = 7 and t = 2
at 2 seconds and again at 7 seconds, the ball will be 224ft in the air.

after how many seconds will the ball hit the ground? we already know this. the ball touches the ground just like the parabola touches the x-axis. to find when the ball hits the ground, we just have to find the root of the parabola, and we already know from earlier that the roots are t=0 and t=9. so, the ball will come into contact with the ground at 9 seconds.

hope this helped

Related Questions

Select the equation that most accurately depicts the word problem. Mary Lou has 2 more nickels than pennies, and she has 30 coins all together. Use x for the number of pennies. 2(x + 2) = 30 x + (x + 2) = 30 2x + 30 = 5 x + 2 = 30
What are the measures of angles QRS and STU ?
Amelia takes her two cats sparkle and twinkle to the vet the vet says that sparkle is 464 mm long and twinkle is 46 cm long which of Amelia's cats is longer EXPLAIN
Identify which table shows a direct variation.A. Table 1 only B. Table 2 only C. both tables D. neither table
7.Write the equation in point-slope form of the line thatpasses through the given point and has the given slope.(4,-7); m = -1/4

I don’t know how to do this

Answers

Answer:

The figure is rotating clockwise

Step-by-step explanation:

Let us revise the cases of rotation

1. Rotation with positive direction (anti-clockwise)

- If the point (x, y) rotated about the origin by angle 90° anti-clockwise

∴ Its image is (-y, x)

- If the point (x, y) rotated about the origin by angle 180° anti-clockwise

∴ Its image is (-x, -y)

- If the point (x, y) rotated about the origin by angle 270° anti-clockwise

∴ Its image is (y, -x)

2. Rotation with negative direction (clockwise)

- If the point (x, y) rotated about the origin by angle 90° clockwise  (-90°)

∴ Its image is (y, -x)

- If the point (x, y) rotated about the origin by angle 180° clockwise  (-180°)

∴ Its image is (-x, -y)

- If the point (x, y) rotated about the origin by angle 270° clockwise  (-270°)

∴ Its image is (-y, x)

From the given

∵ The figure is rotating around the origin by d degrees

∵ d < 0, which means d is negative

→ According to rule 2 above

∴ The direction of rotation is clockwise

The figure is rotating clockwise

Clarise evaluated this expression.(66.3 – 14.62) ÷ 0.6 – 0.22

(51.68) ÷ 0.6 – 0.22

(51.68) ÷ 0.42

51.68 ÷ 0.16

32.3

Which errors did Clarise make? Check all that apply.
1. She subtracted before evaluating the exponents.
2. She evaluated inside the parentheses first.
3. She divided before she subtracted.
4. She subtracted before she divided.
5. She divided incorrectly.

Answers

Answer:

the answer is 2,and 4 and 5

Answer:

yo

Step-by-step explanation:

A,D,E

edgeeeeeeeeeeeee

Diana usually drives at average rate of 30 mph.If Diana drives for two hours with the speed of x mph, what distance will she cover?
PLZZZZZZZZZZZZZ HELP QUICK I WILL MAKE BRAINLIST

Answers

The total distance would be 60 miles traveled by Diana drives for two hours with a speed of 30 mph.

What is Average speed?

Average speed is defined as the ratio of the total distance traveled by a body to the total time taken for the body to reach its destination.

We have been given that Diana usually drives at an average rate of 30 mph.

she drives for two hours with the speed of 30 mph,

To determine the distance will she cover

Average speed = total distance / total time

Here total time = two hours and the average speed = 30 mph

30 mph = total distance / two hours

total distance = 30 × 2

total distance = 60 miles

Therefore, the total distance would be 60 miles traveled by Diana drives for two hours with a speed of 30 mph.

Learn more about the average speed here :

brainly.com/question/12322912

#SPJ2

Answer: 2x

Step-by-step explanation

Its 2x because we  dont know the speed so we just put the x and the 2 is the hours so its 2x.

Solve 4^(2x) = 7^(x−1).

Answers

X= -7........im not going to show the work because its alot

Suppose Richard walks 1 kilometer every 10 minutes.how many meters further can he walk in 1 hour at this new rate?explain how you found your answer.

Answers

This Problem Is Actually Quite Simple If You Look. There Are 60 Minutes In One Hour. A Proportional Relationship Will Help.
10       60
----  =  ---
 1         X

10X = 60. 
-------------
10      10
X = 6. 

Since X = 6, That Means Richard Can Walk 6 kilometers In One Hour. :D
I Hope This Helps You!

Draw a sketch to help you solve this problem. Lucy had 3.2/3 kilograms of apples. She used some of the apples for a dessert. She has 1.1/3 kilogram of apples left.

How much of the apples did Lucy use for her dessert?

Answers

Lucy used 2 1/3 kilograms of apples for her dessert.

Get the whole fraction. 

3 2/3 = ((3*3) + 2) / 3 = 11/3
1 1/3 = ((3*1) + 1) / 3 = 4/3

Original weight of apples = 11/3
Remaining weight of apples = 4/3
weight of apples used = ?

Subtracting fractions:
Step 1. Make sure the denominator are the same

11/3 - 4/3

Step 2. Subtract the numerators and put the difference above the denominator

(11 - 4) / 3 = 7/3

Step 3. Simplify the fraction

7/3 = 2 1/3