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What is the standard form of equation of a circle whose center is #(-5,3)# and radius is #9#?

Answer 1

Sadie Adams

#(x+5)^2+(y-3)^2=9^2#

Standard form of equation of a circle is of the form #(x-h)^2+(y-k)^2=r^2#

Let a point on te circle be #(x,y)#

Now, in a circle point #(x,y)# moves so that its distance from centre #(-5,3)# is always equal to radius which is #9#.

What is the distance of #(x,y)# from #(-5,3)#?

This is #sqrt((x-(-5))^2+(y-3)^2)# and this should be #9#. Hence

#sqrt((x-(-5))^2+(y-3)^2)=9#

or #sqrt((x+5)^2+(y-3)^2)=9#

or #(x+5)^2+(y-3)^2=9^2#

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Answer 2

Sophia Alfred

The standard form of the equation of a circle with center ((-5,3)) and radius (9) is:

[ (x + 5)^2 + (y - 3)^2 = 81 ]

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.