Determining Unknown Angles in Triangles

This video tutorial explains the concept of triangle angles, emphasizing that the sum of angles in any triangle is always 180 degrees. It provides methods to find the third angle when two angles are known, using examples of scalene, right isosceles, and equilateral triangles. The tutorial also highlights the relationships between side lengths and angles in isosceles and equilateral triangles, offering simple calculations to determine unknown angles.

What is the sum of angles in any triangle?

• 270 degrees

• 90 degrees

• 180 degrees

• 360 degrees

Tags

CCSS.8.G.A.5

How can a square help us remember the sum of angles in a triangle?

• Multiply the square's angle sum by 2

• Divide the square's angle sum by 2

• Divide the square's angle sum by 4

• Add 180 to the square's angle sum

What is the sum of the angles in a square?

• 180 degrees

• 360 degrees

• 90 degrees

• 270 degrees

Given two angles of a triangle are 125 degrees and 30 degrees, what is the third angle?

• 45 degrees

• 35 degrees

• 15 degrees

• 25 degrees

Tags

CCSS.8.G.A.5

If a triangle has one angle measuring 90 degrees, what type of triangle could it be?

• Right

• Scalene

• Isosceles

• Equilateral

Tags

CCSS.4.G.A.2

In a scalene triangle with angles of 125 degrees and 30 degrees, what is the sum of the two known angles?

• 150 degrees

• 160 degrees

• 165 degrees

• 155 degrees

Tags

CCSS.8.G.A.5

In a right isosceles triangle, what is the measure of the angles other than the right angle?

• 45 degrees each

• 90 degrees each

• 30 degrees each

• 60 degrees each

Tags

CCSS.8.G.A.5

What property of isosceles triangles helps determine the measure of its angles?

• One angle is always larger than the others

• Two angles are equal

• All angles are equal

• Two angles are always 90 degrees

How many degrees are in each angle of an equilateral triangle?

• 90 degrees

• 45 degrees

• 60 degrees

• 30 degrees

Tags

CCSS.8.G.A.5

What characteristic defines an equilateral triangle?

• None of the sides are equal

• All sides are of different lengths

• Two sides are of equal length

• All sides are of equal length

Tags

CCSS.2.G.A.1