Draw a triangle ABC with side BC = 6.5 cm, ∠B = 30°, ∠A = 105°. Then construct another triangle whose sides are 3/4 times the corresponding sides of the triangle ABC.

Draw a triangle ABC with side BC = 6.5 cm, ∠B = 30°, ∠A = 105°. Then

Question 35 (OR 1st question) - CBSE Class 10 Sample Paper for 2020 Boards - Maths Standard - Part 2
Question 35 (OR 1st question) - CBSE Class 10 Sample Paper for 2020 Boards - Maths Standard - Part 3
Question 35 (OR 1st question) - CBSE Class 10 Sample Paper for 2020 Boards - Maths Standard - Part 4
Question 35 (OR 1st question) - CBSE Class 10 Sample Paper for 2020 Boards - Maths Standard - Part 5 Question 35 (OR 1st question) - CBSE Class 10 Sample Paper for 2020 Boards - Maths Standard - Part 6

 

Note : This is similar to Ex 11.1, 6 of NCERT – Chapter 11 Class 10

Check the answer here https://www.teachoo.com/5748/542/Ex-11.1--6---Draw-a-triangle-ABC-with-side-BC--7-cm--B--45--A--105/category/Ex-11.1/

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Question 35 (OR 1st question) Draw a triangle ABC with side BC = 6.5 cm, ∠B = 30°, ∠A = 105°. Then construct another triangle whose sides are 3/4 times the corresponding sides of the triangle ABC. Let’s first draw a rough diagram To construct Δ ABC, we first need to find ∠ C Finding ∠ C In Δ ABC ∠A + ∠B + ∠C = 180° 105° + 30° + ∠C = 180° 135° + ∠C = 180° ∠C = 180° − 135° ∠C = 45° Steps to draw Δ ABC Draw base BC of side 6.5 cm Draw ∠ B = 30° Draw ∠ C = 45° 4. Let point A be the point where the two rays intersect ∴ Δ ABC is the required triangle Now, we need to make a triangle which is 3/4 times its size ∴ Scale factor = 3/4 < 1 Steps of construction Draw any ray BX making an acute angle with BC on the side opposite to the vertex A. Mark 4 (the greater of 4 and 3 in 3/4 ) points 𝐵_1, 𝐵_2, 𝐵_3,𝐵_4 on BX so that 〖𝐵𝐵〗_1=𝐵_1 𝐵_2=𝐵_2 𝐵_3=𝐵_3 𝐵_4 Join 𝐵_4C and draw a line through 𝐵_3 (the 3rd point, 3 being smaller of 3 and 4 in 3/4) parallel to 𝐵_4 𝐶, to intersect BC at C′. Draw a line through C′ parallel to the line AC to intersect AB at A′. Thus, Δ A′BC′ is the required triangle

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Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.