Exploring the Triangle Sum Theorem with Algebra

The video tutorial explains how to solve a triangle problem using algebra. It begins by introducing the problem and the rule that the sum of angles in a triangle is 180 degrees. The tutorial then sets up an equation using this rule and solves for the variable X. Finally, it verifies the solution by checking the calculated angle measurements to ensure they add up to 180 degrees.

What is the sum of the angles in any triangle?

• 270 degrees

• 360 degrees

• 180 degrees

• 90 degrees

Tags

CCSS.8.G.A.5

If the vertices of a triangle are named A, B, and C, how can we express the sum of the angles?

• A + B + C = 270 degrees

• A + B + C = 180 degrees

• A + B + C = 90 degrees

• A + B + C = 360 degrees

Tags

CCSS.8.G.A.5

What is the expression for angle A given in the problem?

• 9x - 16

• 7x - 5

• 5x + 7

• 3x + 11

Tags

CCSS.8.G.A.5

What is the expression for angle B given in the problem?

• 5x + 7

• 7x - 5

• 3x + 11

• 9x - 16

Tags

CCSS.7.G.B.5

What is the expression for angle C given in the problem?

• 5x + 7

• 3x + 11

• 7x - 5

• 9x - 16

Tags

CCSS.8.G.A.5

After combining like terms, what is the coefficient of x in the equation?

• 16

• 17

• 18

• 19

Tags

CCSS.7.EE.A.1

What is the constant term after combining all the numbers in the equation?

• -10

• -21

• -5

• -16

Tags

CCSS.7.EE.A.1

What is the value of x after solving the equation?

• 20

• 15

• 10

• 5

Tags

CCSS.7.EE.B.4A

What is the measurement of angle A after substituting x = 10?

• 41 degrees

• 90 degrees

• 65 degrees

• 74 degrees

Tags

CCSS.4.MD.C.7

What is the sum of the angles A, B, and C after substituting x = 10?

• 190 degrees

• 180 degrees

• 200 degrees

• 170 degrees

Tags

CCSS.7.G.B.5