Congruence of Triangle - Class 9 Maths MCQ

This set of Class 9 Maths Chapter 7 Multiple Choice Questions & Answers (MCQs) focuses on “Congruence of Triangle – 1”.

1. Given that ∠A = ∠P and AC = PR. Then, which of the following conditions are true for Δ PQR and Δ ABC to be congruent.

a) BC = QR by ASS criteria
b) BC = QR by SSA criteria
c) AB = PQ by SAS criteria
d) AB = PQ by SSA criteria
View Answer

Answer: c
Explanation: If two sides and the included angle of a triangle is equal to the two sides and the included angle of another triangle, then the two triangles are said to be congruent by SAS congruence criteria. Only SAS congruence criteria holds true not ASS or SSA rule.
In Δ PQR and Δ ABC,
∠P = ∠A (given),
AC = PR (given),
Δ PQR and Δ ABC will be congruent by SAS rule only when AB = PQ.

2. Find the angle ∠Q and ∠R if ∠P = 80° and PQ = PR.

a) 60°
b) 50°
c) 30°
d) 90°
View Answer

Answer: b
Explanation: In Δ PQR, ∠P = 80° (Given)
And PQ = PR (Given)
⇒ ∠Q = ∠R (Angles opposite to two equal sides of triangle are equal)
Now, ∠P + ∠Q + ∠R = 180° (Angle Sum property of triangle)
⇒ 80° + 2∠Q = 180° (∠Q = ∠R)
⇒ 2∠Q = 100°
⇒ ∠Q = 50°
Hence, ∠Q = ∠R = 50°.

3. Find the value of angle ABC if AB = BC.

a) 80°
b) 100°
c) 120°
d) 20°
View Answer

Answer: d
Explanation: From Figure, ∠BAC + ∠CAD = 180° (Linear Pair)
⇒ ∠BAC + 100° = 180°
⇒ ∠BAC = 80°
In Δ ABC, ∠BAC = 80° (from above equation)
And AB = BC (Given)
⇒ ∠A = ∠C (Angles opposite to two equal sides of triangle are equal)
∠BAC + ∠ABC + ∠ACB = 180° (Angle Sum property of triangle)
⇒ 80° + ∠B + 80° = 180°
⇒ ∠B = 180° – 160°
⇒ ∠B = 20°.

4. Identify the rule by which the following triangles are congruent.

a) RHS
b) SSS
c) SAS
d) ASA
View Answer

Answer: a
Explanation: From Figure, In Δ PQR and Δ PSR,
∠Q = ∠S = 90° (given),
PQ = PS = 4cm (given), and
PR = PR (Common side)
Hence, Δ PQR is congruent to Δ PSR by RHS Congruence rule.

5. The following triangles are congruent under PRQ ↔ XYZ. Which part of Δ XYZ correspond to PQ?

a) XY
b) YZ
c) XZ
d) YX
View Answer

Answer: c
Explanation: As triangle PRQ is congruent to triangle XYZ,
PR ↔ XY, PQ ↔ XZ, RQ ↔ YZ, and
∠P ↔ ∠X, ∠R ↔ ∠Y, ∠Q ↔ ∠Z (Corresponding parts of congruent triangles)
Hence, Side XZ corresponds to side PQ.

Note: Join free Sanfoundry classes at Telegram or Youtube

6. Which of the following relation is correct if PQ = PS, PR = PT and ∠QPS = ∠TPR?

a) QR = ST
b) QR > ST
c) QR < ST
d) QR = QP
View Answer

Answer: b
Explanation: As it is given that, PQ = PS, PR = PT and ∠QPS = ∠TPR,
∆ PQR is congruent to Δ PST by SAS congruence rule.
Hence, QR = ST (Corresponding parts of congruent triangles).

7. Which among the following relation is correct?

a) Δ ABC ≅ Δ DEF
b) Δ ACB ≅ Δ EFD
c) Δ ABC ≅ Δ FED
d) Δ ACB ≅ Δ FED
View Answer

Answer: d
Explanation: From Figure, In Δ ABC and Δ DEF,
∠BAC = ∠DFE = 40°,
∠ACB = ∠DEF = 60° and
AC = EF
Hence, Δ ACB ≅ Δ FED by ASA congruence criteria.

Sanfoundry Global Education & Learning Series – Mathematics – Class 9.

To practice all chapters and topics of class 9 Mathematics, here is complete set of 1000+ Multiple Choice Questions and Answers.

If you find a mistake in question / option / answer, kindly take a screenshot and email to [email protected]

« Prev - Class 9 Maths MCQ – Angle Sum Property of a Triangle

» Next - Class 9 Maths MCQ – Congruence of Triangle – 2

Related Posts:

Recommended Articles: