Triangle Properties and Angle Calculations

The video tutorial explains how to calculate the side length of an obtuse triangle using two methods: the Pythagorean theorem and the law of sines. The instructor first introduces the problem, describing the triangle's angles and side lengths. In the first method, a right triangle is constructed to apply the Pythagorean theorem, leading to a quadratic equation that is solved to find the side length. The second method involves using the law of sines to find the unknown angle and subsequently the side length. The video concludes with a call to action for viewers to subscribe.

What is the angle BAC in the obtuse triangle ABC?

• 45°

• 60°

• 120°

• 90°

What is the length of side AC in triangle ABC?

• 2

• 4

• 3

• 5

What is the length of side BC in triangle ABC?

• 5

• 3

• 4√3

• 2

Why can't the Pythagorean theorem be directly applied to triangle ABC?

• Because it is a scalene triangle

• Because it is an equilateral triangle

• Because it is not a right triangle

• Because it is not a triangle

What type of triangle is formed by extending side AB to point D?

• Scalene triangle

• Right triangle

• Isosceles triangle

• Equilateral triangle

What is the measure of angle ADC in the right triangle ADC?

• 90°

• 60°

• 30°

• 120°

In a 30-60-90 triangle, how does the longest leg compare to the shortest leg?

• It is the same length

• It is twice the length

• It is half the length

• It is three times the length

What is the length of side AD in the right triangle ADC?

• 1

• 2

• 4

• √3

What is the length of the third leg in the 30-60-90 triangle ADC?

• 1

• 2

• √3

• 4

What is the expression for side length BD in terms of x?

• x + 2

• x

• x + 1

• x - 1