RBSE Solutions for Class 8 Maths Chapter 4 Practical Geometry Ex 4.3

Rajasthan Board RBSE Solutions for Class 8 Maths Chapter 4 Practical Geometry Ex 4.3 Textbook Exercise Questions and Answers.

RBSE Class 8 Maths Solutions Chapter 4 Practical Geometry Ex 4.3

Question 1.
Construct the following qua-drilaterals.
(i) Quadrilateral MORE
MO = 6 cm
OR = 4.5 cm
∠M = 60°
∠O = 105°
∠R = 105°
Answer:
First of all we draw a rough sketch of the required quadrilateral and write down its dimensions.

Steps of Construction:

1. First we draw MO = 6 cm
2. Then we make ∠MOX = 105°
3. With O as centre and radius 4.5 cm, we cut off OR = 4.5 cm along OX.
4. Now we make ∠ORY = 105°
5. We make ∠ZMO = 60° such that arms RY and MZ intersect at E.

Hence we get the required quadrilateral MORE.

(ii) Quadrilateral
PLAN
PL = 4 cm
LA = 6.5 cm
∠P = 90°
∠A = 110°
∠N = 85°
Answer:
First we draw a rough sketch of the required quadrilateral PLAN and write down its dimensions.

Here, ∠PLA = 360° - (90° + 110° + 85°) = 360° - 285° = 75°

Steps of Construction:

1. First we draw PL = 4 cm.
2. Now we make ∠XPL=90°
3. We make ∠YLP = 75°
4. With L as centre and radius 6.5 cm, we cut off LA = 6.5 cm along LY
5. We make ∠ZAL = 110° and let its arm AZ intersect PX at N.

Hence we get the required quadrilateral PLAN.

(iii) Parallelogram HEAR
HE = 5 cm
EA = 6 cm
∠R = 85°
Answer:
We know that the opposite angles of a parallelogram are equal.

We make a rough sketch of the required parallelogram as shown. 

Steps of Construction:

1. First we draw HE = 5 cm.
2. We make ∠HEX = 85°.
3. With E as centre and radius 6 cm, we cut off EA = 6 cm along EX.
4. With A as centre and radius 5 cm, we draw an arc.
5. With H as centre and radius 6 cm, we draw another arc cutting the previous arc at R.
6. Now we join HR and AR.

Hence we get HEAR as the required parallelogram.

(iv) Rectangle
OKAY
OK = 7 cm
KA = 5 cm
Answer:
We know that the opposite sides of a rectangle are equal and each angle of it is 90°.

We make a rough sketch of the required rectangle and write down its dimensions.

Steps of Construction:

1. First we draw OK = 7 cm.
2. Then we draw ∠OKX = 90°.
3. With K as centre and radius 5 cm, we draw an arc KX at A.
4. With A as centre and radius 7 cm, we draw an arc.
5. With O as centre and radius 5 cm, we draw another arc cutting the previous arc at Y.
6. We join AY and OY.

Then, OKAY is the required rectangle.