NCERT Exemplar Problems and Solutions (Part-IB) for CBSE Class 10 Mathematics chapter 6, Triangles, is available here. This part contains only the multiple choice type questions and a detailed solution is provided for each question. These questions will prove to be very helpful while preparing for CBSE Class 10 Board Exam 2017-2018.
Find below the NCERT Exemplar problems and their solutions for Class 10 Mathematics Chapter, Triangles:
Exercise 6.1
Multiple Choice Questions (Q. No. 7-12)
Question. 7 In ΔABC and ΔDEF, ∠B = ∠E, ∠F = ∠C and AB = 3DE then, the two triangles are
(a) congruent but not similar
(b) similar but not congruent
(c) neither congruent nor similar
(d) congruent as well as similar
Answer. (b)
Explanation:
Here, two triangles DABC and DDEF do not satisfy any rule of congruency, (SAS, ASA, SSS), so both are not congruent.
Answer. (a)
Explanation:
Question. 9 If ΔABC ~ ΔDFE, ∠A = 30°, ∠C = 50°, AB = 5cm, AC = 8cm and DF = 7.5cm. Then, which of the following is true?
(a) DE =12cm, ∠F =50°
(b) DE =12cm, ∠F =100°
(c) EF =12cm, ∠D =100°
(d) EF =12cm, ∠D =30°
Answer. (b)
Explanation:
Answer. (c)
Explanation:
And, angle formed by DE and FD is ∠D.
So, ∠B = ∠D
⟹ DABC ~ DEDF (By SAS criterion)
Answer. (a)
Explanation:
As the ratio of area of two similar triangles is equal to the ratio of square of their corresponding sides.
Therefore, we get:
Question. 12 If S is a point on side PQ of a ΔPQR such that PS = QS = RS, then
(a) PR . QR = RS2
(b) QS2 + RS2 =QR2
(c) PP2 + QP2 = PQ2
(d) PS2 + RS2 = PR2
Answer. (c)
Explanation:
