Complete the square to rewrite the following equation. Identify the center and radius of the circle. You must show all work and calculations to receive credit.

x2 − 4x + y2 + 8y = −4

Step-by-step explanation:

First group up similar terms for the sake of clarity

(x2−4x)+(y2+8y)=−4

Complete the square in each group. To find the y2 value, find b from 2ab in each term. Then square it and set it as b2. Whatever you add should be added to the other side as well due to the addition property of equality.

(x2−4x+4)+(y2+8y+16)=−4+4+16

Simplify:

(x−2)2+(y+4)2=16

Identify (h,k) and r. Center is (2, -4) and radius is 4

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step-by-step explanation: