Instructional Video3:20
Curated OER

What are Complementary Angles?

6th - 10th
Supplementary, obtuse, acute, complementary angles. It's good to know what all of these mean, but let's focus on one at a time. Complementary angles always add up to 90 degrees. So if given one angle in a complementary angle problem, the...
Instructional Video3:34
Curated OER

How Do You Find a Missing Angle in a Right Triangle?

6th - 8th
The triangle sum theorem states that the interior angles of a triangle add up to 180 degrees. So it seems logical that if there are two known values given for the interior angles of a triangle, the third value could be found using this...
Instructional Video3:40
Curated OER

How Do You Find Missing Angles in an Isosceles Triangle Using Right Triangles?

6th - 8th
Given an isosceles triangle, and the value of one angle, find the missing values. There are some special properties about isosceles triangles. Use the triangle sum theorem to solve this problem. Watch this video to see how the instructor...
Instructional Video3:21
Curated OER

How Do You Use Complementary Angles to Find a Missing Angle?

6th - 10th
Are complementary angles nice to each other? That's not what complementary means in math. Complementary angles are two angles that add up to 90 degrees and form a right triangle. So if given one value in a problem about complementary...