Complementary Angles and Their Applications

This video tutorial teaches how to use complementary angles to find unknown angle measures. It begins with an introduction to complementary angles and highlights a common mistake students make when solving equations. The tutorial provides examples, such as determining the angle needed to complete a right angle on a piece of paper and finding a second angle when one angle is known. The lesson emphasizes the importance of understanding that complementary angles add up to 90 degrees and demonstrates how to solve for unknown angles using subtraction.

What is the sum of complementary angles?

• 360 degrees

• 180 degrees

• 90 degrees

• 45 degrees

What is a common mistake when solving 12 degrees plus x equals 90 degrees?

• Dividing both sides by 12

• Subtracting 12 from both sides

• Adding 12 to both sides

• Multiplying both sides by 12

If a student incorrectly adds 12 to both sides of the equation 12 + x = 90, what incorrect value of x do they find?

• 78 degrees

• 90 degrees

• 12 degrees

• 102 degrees

In the example with the paper, what angle did Rick draw from the corner?

• 81 degrees

• 90 degrees

• 47 degrees

• 9 degrees

How many degrees does Rick need to adjust his line to make a 90-degree angle with the paper's edge?

• 47 degrees

• 9 degrees

• 81 degrees

• 90 degrees

If one angle is 43 degrees, what is the measure of its complementary angle?

• 47 degrees

• 43 degrees

• 90 degrees

• 37 degrees

What equation represents two complementary angles if one is 43 degrees?

• 43 + x = 180

• 43 + x = 90

• x - 43 = 90

• x + 43 = 180

What is the measure of the second angle if two angles are complementary and one measures 43 degrees?

• 43 degrees

• 90 degrees

• 37 degrees

• 47 degrees

What is the key takeaway from the lesson on complementary angles?

• Complementary angles add up to 90 degrees

• Complementary angles are always different

• Complementary angles add up to 180 degrees

• Complementary angles are always equal

What is the purpose of using complementary angles in solving unknown angle measures?

• To find the sum of angles

• To solve for unknown angle measures

• To compare angles

• To determine the difference between angles