Practice the questions of **McGraw Hill Math Grade 8 Answer Key PDF Lesson 20.1 Triangles: Acute, Right, Obtuse, Equilateral, Isosceles, and Scalene **to secure good marks & knowledge in the exams.

## McGraw-Hill Math Grade 8 Answer Key Lesson 20.1 Triangles: Acute, Right, Obtuse, Equilateral, Isosceles, and Scalene

**Exercises**

**IDENTIFY**

**Identity as acute, right, or obtuse.**

Question 1.

Answer:

Acute Triangle,

Explanation:

An acute angle triangle (or acute-angled triangle) is a triangle in which all the interior angles are acute angles or an acute angle is an angle that is less than 90°.

Given triangle has all interior angles, so it is acute triangle.

Question 2.

Answer:

Obtuse Triangle,

Explanation:

An obtuse-angled triangle is a triangle in which one of the interior angles measures more than 90° degrees. Given triangle one of interior angle measures

more than 90° degrees, so it is obtuse triangle.

Question 3.

Answer:

Right Triangle,

Explanation:

A right angled triangle is a triangle with one of the angles as 90 degrees.

As given triangle has one angle 90 degress so it is right triangle.

Question 4.

Answer:

Acute Triangle,

Explanation:

An acute angle triangle (or acute-angled triangle) is a triangle in which all the interior angles are acute angles or an acute angle is an angle that is less than 90°.

Given triangle has interior angles less than 90 degress so it is acute triangle.

Question 5.

Answer:

Right Triangle,

Explanation:

A right angled triangle is a triangle with one of the angles as 90 degrees.

As given triangle has one angle 90 degress, so it is right triangle.

Question 6.

Answer:

Acute Triangle,

Explanation:

An acute angle triangle (or acute-angled triangle) is a triangle in which all the interior angles are acute angles or an acute angle is an angle that is less than 90°.

Given triangle has all interior angles are acute.

**Identify as isosceles, scalene, or equilateral.**

Question 7.

Answer:

Equilateral Triangle,

Explanation:

All the given sides are 4 and equal so given triangle is equilateral triangle.

Question 8.

Answer:

Isosceles Triangle,

Explanation:

As given triangle has 2 sides with 8 and one side with 4 lengths so it is an isosceles triangle. As an isosceles triangle is a triangle that has any two sides equal in length and angles opposite to equal sides are equal in measure.

Question 9.

Answer:

Scalene Triangle,

Explanation:

Given triangle is a scalene triangle as it has different side lengths so it is

scalene triangle, A scalene triangle is a triangle in which all three sides are in different lengths, and all three angles are of different measures. However, the sum of all the interior angles is always equal to 180 degrees.