Default Title

Question (11)

QN0030163

If the three angles of a triangle are all equal, then the triangle is:

(A) Isosceles only
(B) Equilateral
(C) Scalene
(D) Right-angled

Correct Answer: B

Explanation:

Equal angles imply equal sides.

Link:

Report Error

Question (12)

QN0030164

In an isosceles triangle, each base angle is 37°. The vertex angle is:

(A) 74°
(B) 96°
(C) 106°
(D) 112°

Correct Answer: C

Explanation:

180° − 37° − 37° = 106°.

Link:

Report Error

Question (13)

QN0030165

One angle of an equilateral triangle is increased to 70°. Which statement is correct?

(A) It is still an equilateral triangle.
(B) It becomes an isosceles triangle.
(C) It cannot remain an equilateral triangle.
(D) It becomes a right triangle.

Correct Answer: C

Explanation:

Every angle of an equilateral triangle must be exactly 60°.

Link:

Report Error

Question (14)

QN0030166

In an isosceles triangle, one base angle is twice the vertex angle. What is the vertex angle?

(A) 30°
(B) 36°
(C) 45°
(D) 60°

Correct Answer: B

Explanation:

Let the vertex angle be x. Then x + 2x + 2x = 180°, so x = 36°.

Link:

Report Error

Question (15)

QN0030167

The angles of an isosceles triangle are in the ratio 1 : 1 : 4. What is the largest angle?

(A) 36°
(B) 72°
(C) 120°
(D) 144°

Correct Answer: C

Explanation:

Total parts = 6. One part = 30°. Largest angle = 4 × 30° = 120°.

Link:

Report Error

Question (16)

QN0030168

In an isosceles triangle, each base angle measures 54°. What is the vertex angle?

(A) 54°
(B) 60°
(C) 72°
(D) 84°

Correct Answer: C

Explanation:

Vertex angle = 180° − 54° − 54° = 72°.

Link:

Report Error

Question (17)

QN0030169

The vertex angle of an isosceles triangle is 110°. Each base angle is:

(A) 35°
(B) 45°
(C) 55°
(D) 70°

Correct Answer: A

Explanation:

(180° − 110°) ÷ 2 = 35°.

Link:

Report Error

Question (18)

QN0030170

The angles of an isosceles triangle are in the ratio 2 : 2 : 5. What is the largest angle?

(A) 50°
(B) 80°
(C) 100°
(D) 120°

Correct Answer: C

Explanation:

Total parts = 9. One part = 20°. Largest angle = 5 × 20° = 100°.

Link:

Report Error

Question (19)

QN0030171

An isosceles triangle has a vertex angle of 24°. What is each base angle?

(A) 66°
(B) 72°
(C) 78°
(D) 84°

Correct Answer: C

Explanation:

(180° − 24°) ÷ 2 = 78°.

Link:

Report Error

Question (20)

QN0030172

The angles of an isosceles triangle are in the ratio 3 : 3 : 4. What is each equal angle?

(A) 45°
(B) 50°
(C) 54°
(D) 60°

Correct Answer: C

Explanation:

Total parts = 10. One part = 18°. Each equal angle = 3 × 18° = 54°.

Link:

Report Error

Question (11)

If the three angles of a triangle are all equal, then the triangle is:

Explanation:

Link:

Question (12)

In an isosceles triangle, each base angle is 37°. The vertex angle is:

Explanation:

Link:

Question (13)

One angle of an equilateral triangle is increased to 70°. Which statement is correct?

Explanation:

Link:

Question (14)

In an isosceles triangle, one base angle is twice the vertex angle. What is the vertex angle?

Explanation:

Link:

Question (15)

The angles of an isosceles triangle are in the ratio 1 : 1 : 4. What is the largest angle?

Explanation:

Link:

Question (16)

In an isosceles triangle, each base angle measures 54°. What is the vertex angle?

Explanation:

Link:

Question (17)

The vertex angle of an isosceles triangle is 110°. Each base angle is:

Explanation:

Link:

Question (18)

The angles of an isosceles triangle are in the ratio 2 : 2 : 5. What is the largest angle?

Explanation:

Link:

Question (19)

An isosceles triangle has a vertex angle of 24°. What is each base angle?

Explanation:

Link:

Question (20)

The angles of an isosceles triangle are in the ratio 3 : 3 : 4. What is each equal angle?

Explanation:

Link:

Excel With Tutors

ExcelWithTutors

For Student

For Tutors

Learn

OUR POLICY