AP State Syllabus AP Board 6th Class Maths Solutions Chapter 8 Basic Geometric Concepts Ex 8.4 Textbook Questions and Answers.

## AP State Syllabus 6th Class Maths Solutions 8th Lesson Basic Geometric Concepts Ex 8.4

Question 1.

Measure all the angles in the above figures.

∠1 = 70°

∠3 = 70°

∠5 = 70°

∠7 = 70°

∠2 = 110°

∠4 = 110°

∠6 = 110°

∠8= 110°

∠a = 60°

∠c = 60°

∠e = 50°

∠g = 50°

∠b = 120°

∠d = 120°

∠f = 130°

∠h = 130°

Question 2.

Sum of which two angles is 180° in each figure ?

Solution:

From above question,

i) ∠1 + ∠2 = 180°

i) ∠1 + ∠2 = 180°

∠2 + ∠3 = 180°

∠1 + ∠4 = 180°

∠3 + ∠4 = 180°

∠5 + ∠6 = 180°

∠6 + ∠7 = 180°

∠7 + ∠8 = 180°

∠5 + ∠8 = 180°

∠1 + ∠8 = 180°

∠4 + ∠5 = 180°

∠2 + ∠7 = 180°

∠3 + ∠6 = 180°

ii) ∠a + ∠b = 180°

∠b + ∠c = 180°

∠c + ∠d = 180°

∠a + ∠d = 180°

∠e + ∠f = 180°

∠f + ∠g = 180°

∠g + ∠h = 180°

∠e + ∠h = 180°

Question 3.

In the given figure measure ∠FOG and draw the same in your note book.

Solution:

Question 4.

In the given figure measure the angles ∠AOB, ∠BOC.

Solution:

∠AOB = 110°

∠BOC = 60°

∠AOC = 50°

Question 5.

Write some acute, obtuse and reflexive angles atleast 2 for each.

Solution:

Acute angles : 10°, 30°, 45°, 60°, 89° (< 90°)

Obtuse angles : 110°, 150°, 160°, 172°, 178° (90° < obtuse < 180°) Reflex angles : 210°, 270°, 300°, 345°, 359° (reflex > 180°)