Q. 1 D5.0( 1 Vote )

# Find the coordinates of the centre radius of each of the following circle:

x^{2} + y^{2} – ax – by = 0

Answer :

Given:

equation of the circle is x^{2} + y^{2} - ax - by = 0 .... (1)

We know that for a circle

x^{2} + y^{2} + 2ax + 2by + c = 0 .... (2)

⇒ Centre = (- a, - b)

⇒ Radius =

Comparing (1) with (2) we get,

⇒ Centre =

⇒ Centre =

⇒ Radius =

⇒ Radius =

⇒ Radius =

⇒ Radius =

∴ The centre and radius of the circle is and .

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