Classify Right Triangles

In a ____________ triangle one angle is exactly 90 degrees.

• acute

• right

• obtuse

• 360 degrees

What kind of triangle is this?

• acute

• right

• obtuse

• 360 degrees

What kind of triangle is this?

• acute

• right

• obtuse

• 360 degrees

A triangle has angle measurements of 51°, 39°, and 90°. What kind of triangle is it?

• acute

• right

• obtuse

• 360 degrees

LOOKING AT ANGLES: WHAT TYPE OF TRIANGLE IS THIS? HINT: ONE ANGLE = 90 DEGREES

• ACUTE

• OBTUSE

• RIGHT

Which triangle is a right triangle?

• 
• 
• 

This is a right triangle because —

• it is facing the right way

• it has 3 acute angles

• it has one 90 degree angle

• it does not have one obtuse angle

Use the angles to classify the triangles

Use the angles to classify the triangles

all angles less than 90° - acute triangle

1 angle is equal to 90° - right triangle

1 angle is greater than 90° - obtuse triangle

Use the angles to classify the triangles