Classifying Triangles Worksheet - Page 2

Classifying Triangles Worksheet
• Page 2
11.
Can a triangle be a right as well as an isosceles triangle at the same time?
 a. I don′t know. b. No c. Yes d. Can′t say

Solution:

When one angle of a triangle is equal to 90o, the triangle is known as a right triangle.

A triangle having two sides and 2 angles of equal measures is known as an isosceles triangle.

When one angle of a triangle is equal to 90o and the other two angles are 45o each, the triangle is a right isosceles triangle.

12.
Identify an acute triangle.

 a. Figure 1 b. Figure 2 c. Figure 3 d. Figure 1 and Figure 3

Solution:

When all the three angles of a triangle are less than 90°, the triangle is known as an acute triangle.

Among the choices, figure 2 is an appropriate figure for the acute angled triangle.

13.
Classify the triangle by the measure of the angles.

 a. straight angle b. acute triangle c. right triangle d. obtuse triangle

Solution:

When all angles of a triangle are less than 90°, the triangle is called an acute angled triangle.

In the figure, all of the angles are 60° and are less than 90°. Therefore, the triangle is called an acute triangle.

14.
Which triangle has all its three angles of different measures?
 a. isosceles triangle b. equilateral triangle c. scalene triangle d. none of these

Solution:

In an equilateral triangle, all the three angles are of equal measures.

In an isosceles triangle, two of the angles are of equal measures.

In a scalene triangle, all the three angles are of different measures.

15.
"Two of the angles measure 50o each in a scalene triangle". State whether the statement is true or false.
 a. Can′t say b. I don′t know. c. True d. False

Solution:

In a scalene triangle, all the three angles are of different measures.

The measures of two angles in a scalene triangle cannot measure 50o each.

So, the statement is not correct.

16.
Can a triangle have two angle measures equal to 90o each?
 a. I don′t know b. Yes c. Can′ t say d. No

Solution:

Sum of the three angles in a triangle is 180o.

So, the measure of two angles in a triangle cannot be 90o each.

17.
Find the value of $x$ in the figure.

 a. 8 cm b. 6 cm c. 5 cm d. 7 cm

Solution:

In the figure, all the angles are equal.

So, it is an equilateral triangle.

In an equilateral triangle all sides are equal.

So, the value of x is 5 cm.

18.
Classify the triangle whose sides measure 7 in., 8 in., and 5 in.
 a. equilateral triangle b. right triangle c. isosceles triangle d. scalene triangle

Solution:

None of the side lengths are same.

So, the triangle is a scalene triangle.

19.
Classify the triangle shown by the approximate measure of its angles.

 a. acute b. right c. obtuse d. none of these

Solution:

When all the three angles of a triangle are less than 90°, the triangle is known as an acute angled triangle.

So, the figure represents an acute angled triangle.