Question 1151351
1. Find the equation of the circle with centre (0,0) and
a) with a radius of 7
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A circle's equation is (x-h)^2 + (y-k)^2 = r^2
(h,k) is the Origin ---> h = k = 0
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{{{x^2 + y^2 = 7^2}}}
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b) diameter of 12
r = 6, same as a
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c) passing through (2,-4)
r^2 = 2^2 + 4^2 = 20
same as a