Finding Missing Angle Measures Using Simple Equations and the Triangle Sum Theorem

The video tutorial explains how to find missing angle measures in triangles using simple equations and the triangle sum theorem. It demonstrates solving for unknown angles Y and X by setting up equations based on the theorem that the sum of angles in a triangle is 180°. The tutorial includes steps for combining like terms, isolating variables, and verifying results by substituting back into the original expressions. The process is repeated for two different triangles, ensuring understanding of the method.

What is the sum of the interior angles of any triangle?

• 90 degrees

• 360 degrees

• 180 degrees

• 270 degrees

If one angle of a triangle is 20 degrees and another is 4Y degrees, what is the expression for the third angle if the sum of angles is 180 degrees?

• Y + 20 degrees

• Y - 20 degrees

• Y + 10 degrees

• Y - 10 degrees

After solving the equation 5Y = 170, what is the value of Y?

• 35 degrees

• 36 degrees

• 34 degrees

• 37 degrees

What is the measure of the top angle if Y is 34 degrees and the expression is 4Y?

• 140 degrees

• 136 degrees

• 130 degrees

• 120 degrees

How do you verify the calculated angles of a triangle?

• By checking if they are all equal

• By ensuring their sum is 180 degrees

• By comparing them to a right angle

• By measuring them with a protractor

In the second triangle, if 2X + X + 30 + X = 180, what is the value of X?

• 36.5 degrees

• 37.5 degrees

• 35 degrees

• 38 degrees

What is the measure of the angle represented by 2X if X is 37.5 degrees?

• 70 degrees

• 75 degrees

• 80 degrees

• 85 degrees