# NCERT Solutions for Class 8 Maths Chapter 4 Exercise 4.3

NCERT Solutions for Class 8 Maths Chapter 4 Exercise 4.3 (Ex. 4.3) Practical Geometry free to download in PDF file format updated for CBSE academic session 2020-2021. In this exercise, we will construct quadrilaterals with two given sides and three given angles.

Class 8 Maths ex. 4.3 is easy to solve as compared to other exercises of chapter 4 class 8th Maths. Videos with complete explanation and step by step solving are given with the solutions.## Class 8 Maths Chapter 4 Exercise 4.3 Solution

Class: 8 | Mathematics |

Chapter: 4 | Practical Geometry |

Exercise: 4.3 | NCERT Solution in Hindi and English |

### CBSE NCERT Class 8 Maths Chapter 4 Exercise 4.3 Solution in Hindi and English Medium

### Class 8 Maths Chapter 4 Exercise 4.3 Solution in Videos

##### III. When two adjacent sides and three angles are given.

Construct a quadrilateral PQRS in which PQ = 4.5 cm, ∠PQR = 120°, QR = 3.8 cm, ∠QRS = 100° and ∠QPS = 60°.

First we draw a rough sketch of quad. PQRS and write down its dimensions, as given.

Steps of construction:

Step 1. Draw PQ = 4.5 cm.

Step 2. Make ∠PQX = 120°.

Step 3. With Q as centre and radius 3.8 cm, draw an arc, cutting QX at R.

Step 4. Make ∠QRY = 100°.

Step 5. Make ∠QPZ = 60°

So that PZ and RY intersect each other at the point S.

Then, PQRS is the required quadrilateral.

##### Construct a quadrilateral ABCD in which AB = 5.6 cm, BC = 4 cm, ∠A = 50°, ∠B = 105° and ∠D = 80°.

First we draw a rough sketch of quad. ABCD and write down its dimensions, as given.

Steps of construction:

Step 1. Draw AB = 5.6 cm.

Step 2. Make ∠ABE = 105°

Step 3. With B as centre and radius 4 cm, draw an arc, cutting BE at C.

Step 4. Make ∠BAF = 50° (∠A + ∠B + ∠D = 50° + 105° + 80° = 2350, so, ∠C = 3600 – 2350 = 1250)

Step 5. Make ∠BCD = 125°

So that AF and CG intersect each other at the point D.

Then, ABCD is the required quadrilateral.

##### How do you write an adjacent side?

Adjacent side is the side next to the angle in question. (The one other than the hypotenuse). For example: Here, the side A is adjacent to the angle x.

##### What are adjacent sides and angles?

Two angles are Adjacent when they have a common side and a common vertex (corner point) and don’t overlap. They have a common side (line CB) they have a common vertex (point B).

##### Can 2 adjacent angles be complementary?

Two adjacent angles can be complimentary, if they add up to 90∘, i.e. the sum of two angles formed should be 90∘. They are also complementary as the sum of the angles is 90∘, i.e. ∠ABD+∠CBD=30∘+60∘=90∘.