Central and Inscribed Angles — Practice Set
Recall / Warm-Up
In a circle, the arc intercepted by a central angle measures 84°. What is the measure of the central angle?
A circle has a total arc measure of 360°. A central angle of 120° intercepts minor arc . What is the measure of major arc ?
An angle has its vertex on a circle and its two sides are chords. What type of angle is this?
Fluency Practice
Circle has center . Central angle . What is the measure, in degrees, of minor arc ?
In circle , central angle . What is the measure, in degrees, of minor arc ?
An inscribed angle intercepts an arc of 96°. What is the measure, in degrees, of the inscribed angle?
Inscribed angle measures 37°. What is the measure, in degrees, of intercepted arc ?
Points , , , and lie on a circle in that order. Inscribed angle and inscribed angle both intercept arc (the arc not containing or ). What is the measure of angle ?
Varied Practice
In circle , central angle . Inscribed angle also intercepts arc . What is the measure of inscribed angle ?
Points , , , and lie on a circle in that order. Arc and arc . Point is on arc (the remaining arc). Arc $ZX = $ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ degrees. Inscribed angle , whose vertex is and which intercepts arc (the arc from to going through ), measures ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ degrees.
In circle , the major arc . Inscribed angle has its vertex on the major arc, so it intercepts the minor arc . What is the measure of angle ?
Point is inside circle (not on the circle). Two chords pass through , forming an angle of 40° at . A student claims this is an inscribed angle intercepting an arc of 80°. What error did the student make?
Points and are the endpoints of a diameter of circle . Point lies on the circle. What is the measure, in degrees, of inscribed angle ?
Word Problems / Application
A Ferris wheel has its center at point . Two spokes extend to seats at points and on the rim. The angle between the two spokes (central angle ) is 72°.
A rider at point on the rim of the Ferris wheel sits on the major arc — the longer arc not directly between seats and . What is the measure, in degrees, of inscribed angle ?
In a circular garden design, a designer marks points , , and on a circular path. Arc (not containing ) measures 110°.
The designer wants to place a bench at so that the angle (the view angle from the bench to points and ) equals 55°. What is the measure of inscribed angle ?
Points , , , and lie on a circle in that order. Inscribed angle intercepts arc (the short arc not containing or ) and measures 38°. Inscribed angle also intercepts arc .
What is the measure, in degrees, of inscribed angle ?
What is the measure, in degrees, of arc ?
Triangle is inscribed in a circle. Side is a diameter of the circle. The legs of the triangle measure cm and cm.
What is the diameter of the circle, in centimeters?
Error Analysis
Jordan solved the following problem:
"Points A and B are endpoints of a diameter. Point C lies on the circle. Find angle ACB."
Jordan's work:
- The diameter = 180°.
- Angle ACB = 180° (a straight angle, since AB is a straight line).
What error did Jordan make?
Sam solved the following problem:
"Inscribed angle PQR intercepts major arc PR = 230°. Find angle PQR."
Sam's work:
- Arc PR = 230°.
- Angle PQR = ½ × 230° = 115°.
Is Sam's work correct? If not, identify the error.
Challenge / Extension
In circle , central angle . Point is on the major arc. Point is on the minor arc. Inscribed angle intercepts the major arc . What is the measure, in degrees, of inscribed angle ?
Quadrilateral is inscribed in a circle (a cyclic quadrilateral). Angle . What is the measure, in degrees, of angle ?