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
marin [14]
3 years ago
12

an island has three towns located at points with the coordinates a (15,3) b (25,10) and c (0,20) where the coordinates have unit

s of Km the government wants to locate a toxic waste dump at a position as far as possible away from each town you may assume that this location is not on the edge of the island find the coordinates at the point where the toxic waste dump should be located
Mathematics
1 answer:
julsineya [31]3 years ago
4 0

9514 1404 393

Answer:

  (13.06, 16.41)

Step-by-step explanation:

Any point not on a perpendicular bisector of the line between towns will be closer to one town than the other. So, the intersection of perpendicular bisectors will be the equidistant from all towns. That point is the circumcenter of the circle circumscribing the triangle with the towns as its vertices. This can be found as the intersection of two perpendicular bisectors of the segments between the towns.

The midpoint of AB is ...

  (A +B)/2 = ((15, 3) +(25, 10))/2 = (40, 13)/2 = (20, 6.5)

The midpoint of AC is ...

  (A +C)/2 = ((15, 3) +(0, 20))/2 = (15, 23)/2 = (7.5, 11.5)

__

The differences between points are ...

  B -A = (25, 10) -(15, 3) = (10, 7)

  C -A = (0, 20) -(15, 3) = (-15, 17)

Then the perpendicular bisector equations can be written as ...

  bisector of AB  ⇒  10(x -20) +7(y -6.5) = 0

     10x +7x -245.5 = 0

  bisector of AC  ⇒  -15(x -7.5) +17(y -11.5) = 0

     -15x +17y -83 = 0

These have coefficients that aren't particularly nice, so a method similar to Cramer's Rule is suitable for solving this pair of equations. Using the "cross multiplication method", we have ...

  x = (7(-83) -17(-245.5))/(10(17) -(-15)(7)) = 3592.5/275 = 13 7/110 ≈ 13.06

  y = (-245.5(-15) -(-83)(10))/275 = 4512.5/275 = 16 9/22 ≈ 16.41

The point as far as possible from each town within the boundary of the island has coordinates (13.06, 16.41).

_____

<em>Further detail regarding the solution</em>

Here, we have written the equation for the perpendicular bisector this way. The difference in coordinates between points R and S can be called ...

  R -S = (∆x, ∆y)

The midpoint of segment RS can be called ...

  (R +S)/2 = (h, k)

Then the line that is a perpendicular bisector of RS can be written as ...

  ∆x(x -h) +∆y(y -k) = 0

This is the form that is used above.

__

The "cross multiplication method" for solving a pair of general-form linear equations ...

  ax +by +c = 0

  dx +ey +g = 0

will give the solution as ...

  1/(ae -db) = x/(bg -ec) = y/(cd -ga)

If you write the coefficients in two rows of four, the pattern of products and differences is easy to see.

  \left[\begin{array}{cccc}a&b&c&a\\d&e&g&d\end{array}\right]

You might be interested in
Brainliest to correct answer help
shutvik [7]

Answer:

Step-by-step explanation:

its c trust i am a man in my moms bacement

8 0
2 years ago
Read 2 more answers
Nine more than the product of -8 and a number is -7
Yanka [14]

Answer:

-9

Step-by-step explanation:

5 0
3 years ago
Read 2 more answers
Convert y =(x+1)(x-9) to vertex form
IgorC [24]

Answer:

y = (x - 4)² - 25

Step-by-step explanation:

The equation of a parabola in vertex form is

y = a(x - h)² + k

where (h, k) are the coordinates of the vertex and a is a multiplier

To obtain this form use the method of completing the square.

Given

y = (x + 1)(x - 9) ← expand factors using FOIL, thus

y = x² - 8x - 9

To complete the square

add/subtract ( half the coefficient of the x- term )² to x² - 8x

y = x² + 2(- 4)x + 16 - 16 - 9

  = (x - 4)² - 25 ← in vertex form

5 0
3 years ago
Find 30% decrease from 95<br> 68.40<br> 63.20<br> 66.50
IgorC [24]

Answer:

66.50

stay home and be safe

7 0
3 years ago
Rewrite the following expression using the properties of rational exponents. Be sure your answer is in simplest form.
Fittoniya [83]
4 to the 18th power is the answer to your question. 
3 0
3 years ago
Read 2 more answers
Other questions:
  • Find the sum or difference. (5a – 3b2 – a) + (b – 5 + 8a2)
    14·1 answer
  • I need to find what is equal to m
    11·1 answer
  • Chet bought 3.54 pounds of cheese for his party. If each of his guesis
    8·1 answer
  • One positive number is 5 times another number. the difference between the two numbers is 1140, find the numbers.
    9·1 answer
  • How many paper square with an area of 40 cm² will be needed to form a square with an area of 4 m²?
    8·1 answer
  • Round decimal numbers 8.72
    5·2 answers
  • Can someone solve this for me???
    7·1 answer
  • Determine which method would be more efficient for solving: Rewriting and using the distributive property or dividing. Solve eac
    13·1 answer
  • A grocery store sells a bag of 8 oranges for $4.32. If Colton spent $5.40 on oranges, how many did he but
    14·1 answer
  • Help ASAP please again​
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!