B. Write the equation of the circle in standard form. 1 . 9x 2 + gy ? = 1 6. center at the origin and diameter is 36 cm 2. 9 76 * 2 + - 1612 = 1 7. center at (5, 4) and radius is 15 cm 3. x2 + y2 - 6x - 10y +2=0 8. center at (-4, 8) and passing through the point (1, 4) 4. x2 + y2 + 4x - by - 12=0 9. center at (-2, -4) and tangent to the x-axis 5. center at the origin and radius is 12 cm 10. center at (5, -2) and tangent to the y-axis\fC. Sketch the graph of each circle. Identify the center and the radius. 1. x2 + y2 = 81 3. (x - 8)2 + (y + 3)2 =121 center: center: radius: radius: 2. x2 =36 - yz 4. (x + 4)2 + y2 = 49 center: center: radius: radius: 9