Find the equation in general form of a circle with the center at (4, -1) and radius of 5.
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Solve |
Step |
| r = 5 and (h, k) = (4, -1) | Plug in the values |
| (x - h)2 + (y - k)2 = r2 | Use Standard Equation form |
| (x - 4)2 + (y - (-1))2 = 52 | Simplify |
| (x - 4)2 + (y + 1)2 = 25 | Put in general form |
| x2 - 8x + 16 + y2 + 2y + 1 = 25 | Multiply out |
| x2 + y2 - 8x + 2y + 17 = 25 | Combine like terms and reorder terms |
| x2 + y2 - 8x + 2y - 8 = 0 | Set equal to zero for general form |
| General Form: x2 + y2 + cx + dy + e = 0 | |