What is the radius of a circle whose equation is x2 + y2 + 8x – 6y + 21 = 0? units

The radius of the given circle is 2 units.

Step-by-step explanation: We are given to find the radius of a circle with the following equation:

The STANDARD FORM of a circle with centre at the point (h, k) and radius 'r' units is given by

From equation (i), we have

Comparing this standard equation of the circle with the general standard equation (ii), we get

centre, (h, k) = (-4, 3) and radius, r = 2 units.

Thus, the radius of the given circle is 2 units.

answer by yourhope:

how do models compare to real-world objects?

d. most models represent a real-world object in a simpler way.

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