Learn how to determine the missing variable given an isosceles triangle

The video tutorial demonstrates how to solve for a missing angle in an isosceles triangle. It begins by identifying the properties of isosceles triangles, such as equal sides, and then sets up an equation to find the missing measure. The process involves recognizing congruent sides, forming an equation, and solving for the variable X. The tutorial concludes with the solution, showing that X equals 12.

What is the first step in solving for a missing angle in a triangle?

• Guess the value of the angle

• Use a protractor

• Measure the angle directly

• Set up an equation with a variable

How can you identify an isosceles triangle?

• By finding two sides with tick marks

• By looking for two equal angles

• By checking if all sides are different

• By ensuring all angles are 90 degrees

What equation is set up for the isosceles triangle in the video?

• 3X + 5 = 2X - 7

• 3X - 5 = 2X + 7

• 3X - 7 = 2X + 5

• 3X = 2X + 5

What is the value of X after solving the equation?

• 12

• 10

• 15

• 7

What operation is performed after subtracting 2X from both sides of the equation?

• Add 7 to both sides

• Subtract 5 from both sides

• Multiply both sides by 2

• Add 5 to both sides