Question 1: A circle has its center at point O. The radius of the circle is 5 cm. Calculate the circumference of the circle.

Answer: 31.4

Question 2: Calculate the area of a circle with radius 7 cm. Use π ≈ 3.14.

Answer: 153.86

Question 3: Construct a circle centered at point C with radius 4 cm on the grid.

Answer: Circle with radius 4 cm centered at C

Question 4: Plot the graph of y=2x and draw the circle with radius 3 units centered at the origin. What is the equation of this circle?

Answer: x² + y² = 9

Question 5: A triangle is inscribed in a circle with a radius of 6 cm. If one side of the triangle subtends a 60° arc, what is the length of that side?

Answer: 6√3 ≈ 10.39

Question 6: In a circle, a point P is 3 cm from the center O. Describe the locus of all points that are 4 cm from point P.

Answer: The locus is the set of points that form a circle with radius 4 cm centered at P, but only those points also 3 cm from O are included, forming the intersection of two circles.

Question 7: Find the length of the diameter of a circle with a circumference of 50.24 cm. Use π ≈ 3.14.

Answer: 16 cm

Question 8: Construct a circle with a diameter of 10 cm and mark its center. On the grid, verify the radius length.

Answer: Radius = 5 cm

Question 9: A point P moves such that it remains equidistant from points A and B, which are 8 cm apart. What geometric locus does P trace?

Answer: A perpendicular bisector of the segment AB, which is a line.

Question 10: Identify and correct the mistake in this statement: 'The radius of a circle is equal to its diameter.'

Answer: The radius is half the diameter.

Question 11: A circle with radius 12 cm is inscribed in a square. Calculate the area of the square.

Answer: 144 cm²