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
Vedmedyk [2.9K]
3 years ago
7

Which of the following are true statements about David Hilbert

Mathematics
1 answer:
adoni [48]3 years ago
8 0
Need to know what the options are
You might be interested in
A radio telescope has a parabolic surface, as shown below.
krek1111 [17]
OK, so the graph is a parabola, with points x=0,y=0; x=6,y=-9; and x=12,y=0

Because the roots of the equation are 0 and 12, we know the formula is therefore of the form

y = ax(x - 12), for some a

So put in x = 6

-9 = 6a(-6)

9 = 36a

a = 1/4

So the parabola has a curve y = x(x-12) / 4, which can also be written y = 0.25x² - 3x

The gradient of this is dy/dx = 0.5x - 3

The key property of a parabolic dish is that it focuses radio waves travelling parallel to the y axis to a single point. So we should arrive at the same focal point no matter what point we chose to look at. So we can pick any point we like - e.g. the point x = 4, y = -8

Gradient of the parabolic mirror at x = 4 is -1

So the gradient of the normal to the mirror at x = 4 is therefore 1.

Radio waves initially travelling vertically downwards are reflected about the normal - which has a gradient of 1, so they're reflected so that they are travelling horizontally. So they arrive parallel to the y axis, and leave parallel to the x axis.

So the focal point is at y = -8, i.e. 1 metre above the back of the dish.
5 0
2 years ago
Can someone help me with this one
Viktor [21]

Answer:

y = -4x + (-2)

Step-by-step explanation:

if you plug in the x values in the equation it equals y

4 0
3 years ago
Please help!! A scale on a hiking map shows at 3 inches represents 1.25 miles. What number of inches on the map represents 10 ac
Semenov [28]

Answer:

24 miles

Step-by-step explanation:

Set up a proportion:

3 inches/1.25 miles = x inches/10 miles

Then cross multiply

30=1.25x

Divide 1.25 on both sides

x=24

5 0
3 years ago
A gumball machine has 260 red gumballs. If the red gumballs are 50% of the total number of gumballs, how many gumballs are in th
jek_recluse [69]
520
。・°°・(>_<)・°°・。(´∀`=)
8 0
2 years ago
The actual length (L) of a rectangle is 27 centimeters. Use the scale drawing of the rectangle to find the actual width (W).
nata0808 [166]

Answer:

18 cm

Step-by-step explanation:

The ratio of Actual length (L) to scale length is 27 : 3.6

27 ÷ 3.6 = 7.5

Therefore, actual width (W) = scale width x 7.5

                                              = 2.4 x 7.5

                                              = 18 cm

6 0
2 years ago
Other questions:
  • 49.5 is what percent of 33
    14·1 answer
  • Finding the expression <br> ANSWER ASAP PLEASE!!!!!
    13·1 answer
  • The product of three consecutive<br> numbers CANNOT be:<br> A 210<br> B. 336<br> C. 560<br> D. 1716
    15·1 answer
  • Use the Distributive Property to simplify the expression: 2(4a+6b)
    5·1 answer
  • Does the equation y = x represent a function? Explain why or why not.
    12·1 answer
  • Need help, please 10 pts
    8·1 answer
  • What is the distance between the points (21 , 13) and (3 , 13) in the coordinate plane?
    11·1 answer
  • Simone used 2 1/3 kilograms of flour to bake a cake . She used 4/5 kilograms of flour more to bake a second cake. How much flour
    6·1 answer
  • 20 points! Write an exponential function in the form y=ab^x that goes through points (0, 8) and (2, 200)
    5·2 answers
  • Solve the inequality 2 (m+3) +1 &gt; 23
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!