Answered

Westonci.ca is your trusted source for finding answers to all your questions. Ask, explore, and learn with our expert community. Join our platform to get reliable answers to your questions from a knowledgeable community of experts. Experience the ease of finding precise answers to your questions from a knowledgeable community of experts.

3.a circle of radius 5 units passes through the points (- 3,3) and (3,1) .
i.how many circles can be drawn that meet the given criteria?
ii. what can be the centre of a circle(S)
b. the equation of any two diameters of a circle are given by the straight lines x-y-4=0 and 2x+ 3y + 7 =0.
find the equation of the circle if it passes through the point (2,4).​


3a Circle Of Radius 5 Units Passes Through The Points 33 And 31 Ihow Many Circles Can Be Drawn That Meet The Given Criteriaii What Can Be The Centre Of A Circle class=

Sagot :

Answer:

  • See below

Step-by-step explanation:

Given:

  • Points (- 3,3) and (3,1) on a circle
  • r = 5

i.

There are possible two points that can have a distance of 5 units from both of the given points, so possible two centers, hence two possible circles.

ii.

Let the points are A and B and the centers of circles are F and G.

The midpoint of AB, the point C is:

  • C = ((-3 + 3)/2, (3 + 1)/2) = (0, 2)

The length of AB:

  • AB = [tex]\sqrt{(3 + 3)^2 + (1 - 3)^2} = \sqrt{6^2+2^2} = \sqrt{40} = 2\sqrt{10}[/tex]

The distance AC = BC = 1/2AB = [tex]\sqrt{10}[/tex]

The distance FC or GC is:

  • FC = GC = [tex]\sqrt{5^2-10} = \sqrt{15}[/tex]

Possible coordinates of center are (h, k).

We have radius:

  • (h + 3)² + (k - 3)² = 25
  • (h - 3)² + (k - 1)² = 25

Comparing the two we get:

  • (h + 3)² + (k - 3)² = (h - 3)² + (k - 1)²

Simplifying to get:

  • k = 3h + 2

We consider this in the distance FC or GC:

  • h² + (k - 2)² = 15
  • h² + (3h + 2 - 2)² = 15
  • 10h² = 15
  • h² = 1.5
  • h = √1.5 or
  • h = - √1.5

Then k is:

  • k = 3√1.5 + 2 or
  • k = -3√1.5 + 2

So coordinates of centers:

  • (√1.5, 3√1.5 + 2) for G or
  • (√1.5, 3√1.5 + 2) for F (or vice versa)

-------------------------------------------------------------------------------------

b.

Diameters:

  • x - y - 4 = 0
  • 2x + 3y + 7 = 0

The intercession of the diameters is the center. We solve the system above and get. Not solving here as it is already a long answer:

  • x = 1, y = -3

The point (2, 4) on he circle given.

Find the radius which is the distance between center and the given point:

  • r = [tex]\sqrt{(2 - 1)^2+(4+3)^2} = \sqrt{1^2+7^2} = \sqrt{50}[/tex]

The equation of circle:

  • (x - 1)² + (y + 3)² = 50
View image mhanifa
View image mhanifa