Could somebody please help me solve this?

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2 Answers
Apr 23, 2018

A. #15# units
B. #(-12,-3)#

Explanation:

This equation is in the form #(x-h)^2+(y-k)^2=r^2# where #(h,k)# are the coordinates of the center of the circle and #r# is the radius of the circle. Therefore, for A:

#r^2=225# Square root both sides:
#r=+-15# Distance cannot be negative, so:
A. #r=15# units

For B:
#(h,k)# equals
B. #(-12,-3)# using the form above.

Apr 23, 2018

The equation of a circle is given by #(x−a)^2+(y−b)^2=r^2#,
where#r# is the radius, and (a,b) are the coordinates of the center.

Therefore, comparing the corresponding terms,

#r^2 = 225#
#=>"Radius ", r = sqrt225 =15" units" #

and,
#"Centre would be at "O=(−12,-3)#