Welcome to Westonci.ca, where you can find answers to all your questions from a community of experienced professionals. Explore thousands of questions and answers from a knowledgeable community of experts on our user-friendly platform. Explore comprehensive solutions to your questions from knowledgeable professionals across various fields on our platform.

Consider the equation of a circle x^{2} -2x + y^{2} - 4y - 4 = 0 if the line 2x - y + a = 0 is its diameter. then find the value of a?

Sagot :

Answer:

Step-by-step explanation:

Find the centre first by reoriganisation it into the form (x - cx)^2 + (y -cy)^2 = r^2

x^2 + y^2 + 6x -6y +5 = 0

(x + 3)^2 - 9 + (y - 3)^2 - 9 + 5 = 0

(x + 3)^2 + (y - 3)^2 = 13

The radius does not matter the centre is ( -3, +3)

The diameter must pass through the center so substituting into the equation for the line

2x-y+a = 0

-6 -3 + a = 0 so a = 9

The value of 'a' is 0 and this can be determined by using the standard form of the equation of a circle.

Given :

Equation of a Circle --   [tex]x^2-2x+y^2-4y-4=0[/tex]

Equation of a Line -- 2x - y + a = 0

The following steps can be used in order to determine the value of 'a':

Step 1 - First make the equation of a circle in standard form.

[tex]x^2-2x+y^2-4y-4=0[/tex]

[tex](x-1)^2-1+(y-2)^2-4-4=0[/tex]

[tex](x-1)^2+(y-2)^2 = 3^2[/tex]

Step 2 - From the above step, it can be concluded that the center of the circle is (1,2).

Step 3 - If (1,2) is the center of the circle then it also satisfies the equation of diameter (2x - y + a = 0).

2x - y + a = 0

2(1) - 2 + a = 0

a = 0

For more information, refer to the link given below:

https://brainly.com/question/23528207