Class 6 - Mathematics
Chapter - Practical Geometry : Exercise 10.4
Top Block 1
Question : 1.Construct ΔABC, given 𝓂∠A = 60o,𝓂∠B = 30o and AB = 5.8 cm.
Answer :
To construct: ΔABC where 𝓂∠A = 60o,𝓂∠B = 30o and AB = 5.8 cm.
(a) Draw a line segment AB = 5.8 cm.
(b) At point A, draw an angle ∠YAB = 60o with the help of compass.
(c) At point B, draw ∠XBA = 30o with the help of compass.
(d) AY and BX intersect at the point C.
It is the required triangle ABC.
Question : 2.Construct ΔPQR if PQ = 5 cm, 𝓂∠PQR = 105o and 𝓂∠QRP = 40o.
Answer :
Given: 𝓂∠PQR = 105o and 𝓂∠QRP = 40o
We know that sum of angles of a triangle is 180o.
Mddle block 1
⇒ 105o+40o+𝓂∠QPR = 180o
⇒ 145o + 𝓂∠QPR = 180o
⇒𝓂∠QPR = 180o– 145o
⇒𝓂∠QPR = 35o
Question : 3.Examine whether you can construct ΔDEF such that EF = 7.2 cm, 𝓂∠E = 110o and 𝓂∠F = 80o. Justify your answer.
Answer :
To construct: ΔPQR where 𝓂∠P = 35o, 𝓂∠Q = 105o and PQ = 5 cm.
Steps of construction:
(a) Draw a line segment PQ = 5 cm.
(b) At point P, draw ∠XPQ = 35o with the help of protractor.
(c) At point Q, draw ∠YQP = 105o with the help of protractor.
(d) XP and YQ intersect at point R.
It is the required triangle PQR.