1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Vladimir79 [104]
3 years ago
7

a small rocket is shot from the edge of a cliff suppose that after t seconds the rocket is y meters above the cliff where y=30t-

5t^2 what’s the greatest height the rocket reached? after how many seconds does the rocket reach its height? how far above the cliff edge is the rocket after 5 seconds? when is the rocket 40 meters above the cliff edge? where is the rocket after 7 seconds?
Mathematics
1 answer:
Natalka [10]3 years ago
5 0

Answer:

Greatest height: 45 meters

Time for greatest height: 3 seconds

Height after 5 seconds: 25 meters above the cliff

Time for height of 40 meters: 7.123 seconds

Height after 7 seconds: -35 meters (35 meters below the cliff)

Step-by-step explanation:

to find the maximum height, we need to calculate the derivative of y in relation to t and then find when dy/dt = 0:

dy/dt = 30 - 10t = 0

10t = 30

t = 3 seconds

In this time, the height is:

y = 30*3 - 5*3^2 = 45 meters

After 5 seconds, the height is:

y = 30*5 - 5*5^2 = 25 meters

The time for the height of 40 meters is:

40 = 30t - 5t^2

t^2 - 6t - 8 = 0

Using Bhaskara's formula, we have:

Delta = 6^2 + 4*8 = 68

sqrt(Delta) = 8.246

t1 = (6 + 8.246) / 2 = 7.123 seconds

t2 = (6 - 8.246) / 2 = -1.123 seconds (negative value for time is not valid)

So the time when the rocket reaches 40 meters is 7.123 seconds

After 7 seconds, the height is:

y = 30*7 - 5*7^2 = -35 meters

The rocket will be 35 meters below the cliff.

You might be interested in
Please help me !!!!!!!!!!!!!
Ostrovityanka [42]
Umm i would not trust that file
5 0
3 years ago
Please help me in this question
Marrrta [24]

Answer:

option c

Step-by-step explanation:

option c is right..

3 0
3 years ago
What is the unit rate of 1/4 kilometer in 1/3 hour
Sever21 [200]

Answer:

0.75km/h

Step-by-step explanation:

4 0
3 years ago
Read 2 more answers
What 2 numbers add to get 2 and multiply to 4
rusak2 [61]
Factor 4
4=1 times 4
2 times 2
they don't add to 2
set up equation
x+y=2
xy=4

first equation, subtract x from both sides
y=2-x
subsitute for y
x(2-x)=4
distribute
2x-x^2=4
add x^2
2x=x^2+4
subtract 2x
0=x^2-2x+4
use quadratic formula which is
if you have ax^2+bx+c=0 then
x=\frac{ -b+/-\sqrt{b^{2}-4ac} }{2a} so

1x^2-2x+4=0
a=1
b=-2
c=4
x=\frac{ -(-2)+/-\sqrt{(-2)^{2}-4(1)(4)} }{2(1)}
x=\frac{ 2+/-\sqrt{4-16} }{2}
x=\frac{ 2+/-\sqrt{-12} }{2}
we have \sqrt{-12} and that doesn't give a real solution
therefor there are no real solutions
but if you want to solve fully
x=\frac{ 2+/-2\sqrt{-3} }{2}
i=\sqrt{-1}
x=\frac{ 2+/-2i\sqrt{3} }{2}
x=1+/-i\sqrt{3}
x=1-i\sqrt{3} or x=1+i\sqrt{3} (those are the 2 numbers)

 





6 0
3 years ago
Please help I’m really stuck on a question.?.? Pleas no links they do not work? Thank you.
creativ13 [48]
Answer: X=18

Explanation: 42 - 18 = 24
24 multiplied by 2 = 48
7 0
3 years ago
Other questions:
  • Find the missing base (b1) of the trapezoid. Dimensions are in CM.
    6·1 answer
  • Need help with this question please!
    14·1 answer
  • What is the difference from the point (-6,2) to the point (2,17)?
    6·1 answer
  • 800,000+6,000+300+2 word form
    8·2 answers
  • Sophie pays m dollars to rent a car for the weekend. On the drive home, she buys $25 worth of gasoline. Her friend Melody pays f
    11·1 answer
  • X + 2y = 72 what are my x and y points on a graph for this equation? please explain
    10·1 answer
  • What is the volume of a cube with a side length of<br> of a unit?
    13·1 answer
  • There are 6 yellow hexagons 2 red trapezoids and 9 green triangles how many flowers could you make if they were changed 30 yello
    11·1 answer
  • Factorise completely x^3+6x^2+3x-10
    13·2 answers
  • Use Special Triangle Shortcuts to find the values of x and y in the first figure. Explain how you determined the length of segme
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!