Determining Acute, Obtuse, & Right Triangles

Acute, Obtuse or Right?

Using the Pythagorean Theorem to classify triangles.

Dr. Tom Giles

Acute, Obtuse or Right?

Multiple Choice

Please classify the triangle with sides 4, 11 and 9.

• Acute

• Obtuse

• Right

Multiple Choice

Please classify the triangle with sides 43, 43, 43

• Acute

• Obtuse

• Right

Multiple Choice

Please classify the triangle with sides 12, 9 and 4

• Acute

• Obtuse

• Right

Multiple Choice

Please classify the triangle with sides

$$4,\ 2\sqrt{15},\ 6$$  

• Acute

• Obtuse

• Right

Multiple Choice

Please classify the triangle with sides

$$\sqrt{13},\ \sqrt{5},\ \sqrt{12}$$  

• Acute

• Obtuse

• Right

Multiple Choice

Please classify the triangle with sides

$$\sqrt{13},\ \sqrt{5},\ \sqrt{8}$$  

• Acute

• Obtuse

• Right

Multiple Choice

Please classify the triangle with sides

$$\frac{\sqrt{3}}{5},\ \frac{\sqrt{6}}{5},\ \frac{3}{5}$$  

• Acute

• Obtuse

• Right