Lesson 22 Instructional Book pg. 220-223

What is the distance from the center to the rim of the fountain?

What type of triangle is the window frame?

How do you know?

What is the diameter, d, of the table?

Which triangle is a right triangle?

• Triangle J

• Triangle K

• Triangle L

• Triangle M

Lian chose A as the correct answer. How did he get that answer?

Tell whether each sentence is true or false:

Groups:

(a) True

,

(b) False

• An obtuse triangle has one angle that measures 90 degrees or more.

• The diameter of a circle is longer than its radius.

• Any radius on the same circle will extend from the center of the circle.

• Knowing the measure of 1 angle is always enough to identify an acute, obtuse or right triangle.

Which group of angle measures describes an acute triangle? Select all that apply.

What is the radius, r, of Jelani's circle?

Label each triangle. Is it an obtuse triangle or a right triangle?

b

c

d

a

Obtuse triangle

Right triangle

Right triangle

Acute triangle