Types of Angles
Triangles by Side Length
Measuring Angles
Angle Relationships
Symbols
100
This angle measures less than 90°.
What is an ACUTE angle?
100
A triangle with all three sides different.
What is a SCALENE TRIANGLE?
100
The measure of the angle in diagram 1.
What is 75°?
100
Complementary angles have a sum of this measure.
What is 90°?
100
This symbol is used for a right angle.
What is a square?
200
A triangle with one angle measuring greater than 90°.
What is an OBTUSE TRIANGLE?
200

This type of triangle can have more than one name.

What is an EQUILATERAL TRIANGLE?

200
The measure of the angle in diagram 2.
What is 178°?
200
Supplementary angles have a sum of this measure.
What is 180°?
200
This symbol is used for an angle.
What is ∠ ?
300
Every triangle has this many degrees in the interior angles.
What is 180°?
300
True or False: A triangle with sides 5in, 7in, 3in can be constructed.
TRUE
300
A triangle with angles 25° and 25° and 130° will be what type of triangle?
What is OBTUSE?
300
The complement and supplement of 72° are these measures.
What are 18° and 108°?
300
This symbol is used for congruent side lengths.
What are tick marks?
400
The missing angle in a right triangle, with one other angle measuring 30°.
What is a 60° angle?
400
The possible side length if the two shorter sides are 2in and 4in.
What are sides less than 6in, but more than 2in?
400
A triangle has an angle measuring 15° and another measuring 85°, this is the third angle.
What is 80°?
400
The complement and supplement of 110° are these measures.
What is "Not possible" and 70°?
400
When finding the area of a triangle, the units are measured this way.
What is units squared?
500
An isosceles triangle has one acute angle measuring 20°. The other two angles are congruent, because the triangle is isosceles.
What are 80° each?
500
A triangle is labeled with side lengths of "a", "a", and "b". This is the perimeter.
What is 2a + b units?
500
This tool is used to measure and draw angles.
What is a protractor or six-in-one?
500
The complement of this angle is 52° and the supplement is 142°.
What is 38°?
500
This symbol is used for a ray.
What is a ⇾ ?
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