# Algebra

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State the center and the radius of the circle represented by the equation

(x + 1)^2 + (y – 5)^2 = 64

• Algebra -

in the general equation of a circle
(x-h)^2 + (y-k)^2 = r^2
the centre is (h,k) and the radius is r

can you match this with your given equation?

• Algebra -

ok based on that I would say the radius is 8 cause 8*8 = 64 and the center is (1,5)? Or do the signs change because of the equation
(x-h)^2 + (y-k)^2 = r^2 making the center (-1,5)?

• Algebra -

the centre is (-1,5)

• Algebra -

That is what I thought, so the standard form would be

(x-(-1]^2 + (y-5)^2 = 64

• Algebra -

yes,
I just mentally change the sign I see in the bracket

• Algebra -

Great! Thanks for the help! So R= 8 and the center is (-1,5) got it! Thanks again!

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