**An obtuse angle is an angle that measures more than****$90°$**** degrees, but less than** **$180°$**** degrees.**

Acute angles can appear in triangles, parallelograms, and other geometric shapes.

**Obtuse Angle **

**An obtuse angle is an angle that measures more than****$90°$**** degrees, but less than** **$180°$**** degrees.**

Acute angles can appear in triangles, parallelograms, and other geometric shapes.

**Obtuse Angle **

True or false?

One of the angles in a rectangle may be an acute angle.

True or false?

One of the angles in a rectangle may be an acute angle.

One of the properties of a rectangle is that all its angles are right angles.

Therefore, it is not possible for an angle to be acute, that is, less than 90 degrees.

False

True or false?

An acute angle is smaller than a right angle.

The definition of an acute angle is an angle that is smaller than 90 degrees.

Since an angle that equals 90 degrees is a right angle, the answer is correct.

True

If the two adjacent angles are not equal to each other, then one of them is obtuse and the other acute.

The answer is correct because the sum of two acute angles will be less than 180 degrees and the sum of two obtuse angles will be greater than 180 degrees

True

Which figure depicts a right angle?

A right angle is equal to 90 degrees. In diagrams A+C, we see that the angle symbol is a symbol representing an angle that equals 90 degrees.

Choose the appropriate triangle according to the following:

Angle B equals 90 degrees.

Let's note in which of the triangles angle B forms a right angle, meaning an angle of 90 degrees.

In answers C+D, we can see that angle B is smaller than 90 degrees.

In answer A, it is equal to 90 degrees.

Test your knowledge

Question 1

True or false?

The sum of two acute angles can be greater than 180 degrees?

Question 2

True or false?

An acute angle is smaller than a right angle.

Question 3

The sum of the adjacent angles is 180

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