06 Circles

Question 1

What is the equation of a circle with centre (0,0)?

Answer 1

X squared + Y squared = R squared

Question 2

What is the equation of a circle with the centre (a,b)?

Answer 2

(X-a) squared + (Y-b) squared = R squared

Question 3

How do you find the equation of a circle from two quadratics?

Answer 3

By completing the square.

Question 4

What is the tangent of a circle perpendicular to?

Answer 4

the radius of the circle.

Question 5

What point does the perpendicular bisector of a chord pass through?

Answer 5

The centre of the circle.