You visited us 1 times! Enjoying our articles? Unlock Full Access!

Equation of Family of Circles Passing through Two Points

Radius of the...

Question

Radius of the circle $x^{2} + y^{2} - 4 x + 2 y - 45 = 0$

5 \sqrt{2}

units

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

4 \sqrt{2}

units

No worries! We‘ve got your back. Try BYJU‘S free classes today!

3 \sqrt{5}

units

No worries! We‘ve got your back. Try BYJU‘S free classes today!

4 \sqrt{5}

units

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is A $5 \sqrt{2}$ units
Given circle is $x^{2} + y^{2} - 4 x + 2 y - 45 = 0$
this is of the form $x^{2} + y^{2} + 2 g x + 2 f y + c = 0$ , where
$(2 g = - 4; 2 f = 2) \Rightarrow (g = - 2; f = 1), c = - 45$
radius $= \sqrt{g^{2} + f^{2} - c} = \sqrt{{(- 2)}^{2} + 1^{2} + 45} = \sqrt{50} = 5 \sqrt{2}$

Suggest Corrections

Similar questions

x^{2} + y^{2} + 2 x + 8 y + 8 = 0

r

y^{2} = 4 x

32

r

x^{2} + y^{2} - 4 x - 2 y - 11 = 0

(4, 5)

7

x -

- 2

x -

2 x^{2} + 2 y^{2} + 3 x - 4 y + 5 = 0

2 \sqrt{5}

Join BYJU'S Learning Program