Equations of Circles (centre origin)

Select the circle with equation:

 $x^2+y^2=4$  

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Select the circle with equation:

 $x^2+y^2=9$  

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Select the equation of a circle with a radius of 5

•  $x^2+y^2=5$  

•  $x^2+y^2=25$  

•  $x^2+y^2=10$  

•  $x^2+y^2=2.5$  

Select the equation of a circle with a radius of 10

•  $x^2+y^2=5$  

•  $x^2+y^2=100$  

•  $x^2+y^2=10$  

•  $x^2+y^2=20$  

Select the equation of a circle with a radius of 6

•  $x^2+y^2=12$  

•  $x^2+y^2=6$  

•  $x^2+y^2=36$  

•  $x^2+y^2=3$  

Select the equation of a circle with a radius of 7

•  $x^2+y^2=14$  

•  $x^2+y^2=7$  

•  $x^2+y^2=49$  

•  $x^2+y^2=3.5$  

Which description matches the equation?

 $x^2+y^2=64$  

• A circle with a centre at (0, 0) and a radius of 8

• A circle with a centre at (0, 0) and a radius of 64

• A circle with a centre at (0, 0) and a radius of 16

• A circle with a centre at (0, 0) and a radius of 32

Which description matches the equation?

 $x^2+y^2=9$  

• A circle with a centre at (0, 0) and a radius of 3

• A circle with a centre at (0, 0) and a radius of 9

• A circle with a centre at (0, 0) and a radius of 81

• A circle with a centre at (9, 9) and a radius of 3

Select all true statements about the graph with the equation

 $x^2+y^2=7$  

• This circle has a centre at the origin

• This circle has a centre at (0, 0)

• The radius of this circle is 7

• The radius of this circle is  $\sqrt{7}$  

Select all true statements about the graph with the equation

 $x^2+y^2=1$  

• This circle has a centre at the origin

• This circle has a centre at (1, 1)

• The radius of this circle is 1

• The point (1, 1) lies inside this circle