Angle Basics
What do you call an angle that measures less than 90 degrees?
An acute angle
What fraction of a circle does a quarter turn represent?
1/4
What is the unit used to measure angles?
degrees
If an angle is split into two parts 30° and 45°, what is the measure of the whole angle?
75 Degrees
Name the point where two rays meet to form an angle.
Vertex
If the minute hand moves from 12 to 6, what fraction of a circle did it turn? Is that clockwise or counterclockwise?
1/2 Clockwised
How many degrees are in a right angle?
90 degrees
Two angles form a straight angle. One is 89°. What is the measure of the other?
91 degrees
Tell whether an angle that measures 90° is acute, right, or obtuse.
Right
Describe a 3/4 turn of the minute hand on a clock (start at 12 — where does it end?).
9
Use benchmark angles to estimate: Which benchmark is closest to an angle that looks about 60°?
Right angle-90 degrees
An angle of 90° is divided into three equal angles. What is the measure of each small angle?
30 degrees
Classify three types of angle measures shown in the benchmark list (30°, 45°, 60°, 90°, 180°).
acute, right, straight
A shaded sector shows 1/10 of a circle. How many degrees does that sector measure?
36 degrees
An angle measures 135°. Is it acute, right, or obtuse? Explain using benchmark angles.
obtuse- it is more than 90 and less than 180
Given three adjacent angles around a point measure 78°, 55°, and 27°, write an equation and find the total angle measure.
78+55+27=160
Explain how two rays form an angle using the words "vertex" and "rays."
Ray AB and Ray BC meet at point B.
If an angle turns through 1/3 of a circle, show the fraction as /360 and find its degree measure.
120 degrees
Explain why an angle that turns through 1/360 of a circle is 1 degree, and use that to compute how many degrees are in 3/4 of a circle.
Because there are 360 degrees in a circle. 3/4=270 degrees
A square's corner (90°) is cut so one piece is 45°. Write an equation and find the remaining angle.
90-45=45