Find the Angle on Unit Circle

A ____ angle is an angle whose vertex is a the center of a circle.

• supplementary

• complimentary

• central

• obtuse

What is the value of θ, theta, in degrees on the unit circle?

• 30°

• 45°

• 60°

• 90°

What is this angle in radians?

• undefined

Answer explanation

• undefined

Answer explanation

• 1
• 2
• 3
• 4

Using θ as a reference angle, mark the triangle sides as Opp, Adj, and Hyp. Label these on the triangle on your paper.

• Hyp

• OP

• Opp

• y

• Adj

• x

Using θ as a reference angle, mark the triangle sides as Opp, Adj, and Hyp. Label these on the triangle on your paper.

• Opp

• x

• Hyp

• y

• Adj

• OP

The Unit Circle has four quadrants such that:

• All quadrants have 90 degrees

• Quadrant IV is between π and 3π/2 radians

• Quadrant III is between 3π/2 and 2π and radians

• Quadrant I is where the acute angles are