Chapter 8, Problem 2P

Classify angles.	(a)	(a) ∡DEF is _____
	(b)	(b) ∡GHI is _____
	(c)	(c) ∡JKL is _____

To determine

To classify: The angle DEF as acute, obtuse, or right.

Answer to Problem 2P

The angle DEF is $\underset{\_}{\text{acute}}$.

Explanation of Solution

Definition used:

An angle is acute when the measure of the angle is in between $0°\text{ to 9}0°$.

An angle is right when the measure of the angle is exactly $\text{9}0°$.

An angle is obtuse when the measure of the angle is in between $90°\text{ to 18}0°$.

Calculation:

Note that the measure of the given angle is less than $\text{9}0°$ but greater than $0°$.

Thus by the above definition, the angle DEF is $\underset{\_}{\text{acute}}$.

To determine

To classify: The angle GHI as acute, obtuse, or right.

Answer to Problem 2P

The angle GHI is $\underset{\_}{\text{obtuse}}$.

Explanation of Solution

Definition used:

An angle is said to be acute when the measure of the angle is in between $0°\text{ to 9}0°$.

An angle is said to be right when the measure of the angle is exactly $\text{9}0°$.

An angle is said to be obtuse when the measure of the angle is in between $90°\text{ to 18}0°$.

Calculation:

Note that the measure of the given angle is less than $180°$ but greater than $\text{9}0°$.

Thus by the above definition, the angle GHI is $\underset{\_}{\text{obtuse}}$.

To determine

To classify: The angle JKL as acute, obtuse, or right.

Answer to Problem 2P

The angle JKL is $\underset{\_}{\text{right}}$.

Explanation of Solution

Definition used:

An angle is said to be acute when the measure of the angle is in between $0°\text{ to 9}0°$.

An angle is said to be right when the measure of the angle is exactly $\text{9}0°$.

An angle is said to be obtuse when the measure of the angle is in between $90°\text{ to 18}0°$.

Calculation:

Note that the measure of the angle JKL is exactly $\text{9}0°$.

Thus by the above definition, the angle JKL is $\underset{\_}{\text{right}}$.