college algebra

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write the equation of the circle in standard form find the center radius, intercept and graph circle
x^2 +y^2+8x+2y+8=0

• college algebra -

rearrange things a bit to get

x^2+8x + y^2+2y = -8
Now complete the squares:
x^2+8x+16 + y^2+2y+1 = -8 + 16 + 1
(x+4)^2 + (y+1)^2 = 9

center at (-4,-1)

when y=0,
(x+4)^2 + 1 = 9
(x+4) = ±√8
x = -4 ± √8

similarly for y when x=0

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