Circle Geometry

What is the circumference of a circle with a radius of 7 cm?

• 21.99 cm

• 50.24 cm

• 28.26 cm

• 43.98 cm

If the diameter of a circle is 10 m, what is its area?

• 78.54 m²

• 31.42 m²

• 100 m²

• 50.27 m²

Using the theorem of intersecting chords, if two chords intersect inside a circle, how do you find the lengths of the segments?

• AE * EB = CE * ED

• AE + EB = CE + ED

• AE - EB = CE - ED

• AE / EB = CE / ED

What is the equation of a circle with center at (3, -2) and radius 5?

• (x + 3)² + (y - 2)² = 25

• (x - 3)² + (y - 2)² = 20

• (x + 3)² + (y + 2)² = 30

• (x - 3)² + (y + 2)² = 25

If a circle has a center at the origin and passes through the point (4, 0), what is its equation?

• x² + y² = 20

• x² + y² = 12

• x² + y² = 16

• x² + y² = 8

Calculate the length of an arc of a circle with a radius of 6 cm and a central angle of 60 degrees.

• 5 cm

• 4π cm

• 2π cm

• 3π cm

Using the Pythagorean theorem, how can you find the distance from a point to the center of a circle?

• d = √((x1 - h)² + (y1 - k)²)

• d = (x1 + h) + (y1 + k)

• d = (x1 - h)² + (y1 - k)²

• d = |x1 - h| + |y1 - k|

If two tangents are drawn from a point outside a circle, how do you find the lengths of those tangents?

• Length of each tangent = √(d² - r²)

• Length of each tangent = d + r

• Length of each tangent = 2r

• Length of each tangent = d - r

What is the relationship between the angles formed by two intersecting chords in a circle?

• The angles are equal to the difference of the measures of the arcs they intercept.

• The angles are equal to the sum of the measures of the arcs they intercept.

• The angles formed by two intersecting chords are equal to half the sum of the measures of the arcs they intercept.

• The angles are equal to the measures of the intercepted arcs.

If a circle is inscribed in a triangle, how do you find the radius of the circle?

• r = 2A / s

• r = s / A

• r = A * s

• r = A / s