Equation of a circle
Types of exercises: centre and radius from the equation, equation of a circle from centre and radius, a circle and the coordinate axes, circle through a given point, position of a point relative to a circle.
Exercises are drawn at random from a large bank - every click gives a different set.
Solved: 0 of 10
Which equation describes this circle?
A circle has centre (−9, −10) and radius 19.
How many points does this circle have in common with the x-axis?
(x + 4)² + (y + 9)² = 81
Give the radius of the circle
(x − 12)² + (y − 4)² = 225
Which equation describes this circle?
A circle with centre S = (−3, −1) passes through the point A = (−10, 2).
Which equation describes this circle?
A circle has centre (9, −8) and radius 2.
How many points does this circle have in common with the x-axis?
(x − 6)² + (y + 1)² = 1
Give the radius of the circle
(x + 4)² + (y − 5)² = 196
Give the radius of this circle
A circle with centre S = (6, −6) passes through the point A = (−3, 6).
Which equation describes this circle?
A circle has centre (−12, 12) and radius 20.
Give the radius of the circle
A circle with centre S = (7, 5) is tangent to the x-axis.
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