Geometry Questions

Multiple choice
  1. 7

  2. 9

  3. 12

  4. 14

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

For any circle, if AB is a diameter and PT is a tangent from external point P, then PT² = PA × PB. This is the power of a point theorem. Given AB = 7, PT = 12. Let PA = x, then PB = PA + AB = x + 7. So: 12² = x(x + 7). 144 = x² + 7x. x² + 7x - 144 = 0. (x + 16)(x - 9) = 0. Therefore x = 9. Option A (7) would be the diameter itself, not PA.

Multiple choice
  1. 9 cm./सेमी.

  2. 7 cm./सेमी.

  3. 23 cm./सेमी.

  4. 11 cm./सेमी.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

For chord length L in a circle of radius R, perpendicular distance from center = sqrt(R² - (L/2)²). For 30 cm chord: distance = sqrt(289 - 225) = 8 cm. For 16 cm chord: distance = sqrt(289 - 64) = 15 cm. Since both chords are on same side of center, distance between them = 15 - 8 = 7 cm.

Multiple choice
  1. 53o

  2. 43o

  3. 40o

  4. 37o

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

AB is a diameter, so ∠ABC = 90° (angle in semicircle). Given ∠AOD = 106° (central angle), arc AD = 106°. ∠ABD = 106°/2 = 53° (inscribed angle on same arc). In right triangle ABC: ∠ABC + ∠BCD = 90°, so ∠BCD = 90° - 53° = 37°.

Multiple choice
  1. 18 cm./सेमी.

  2. 20 cm./सेमी.

  3. 24 cm./सेमी.

  4. 36 cm./सेमी.

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

By tangent-secant theorem: PT² = OP² - OT² (since OT ⟂ PT). Given OP = 26 cm and PT = 10 cm, we have OT² = 26² - 10² = 676 - 100 = 576. Thus OT = √576 = 24 cm. The radius is perpendicular to the tangent at the point of contact.

Multiple choice
  1. 8 cm

  2. 15 cm

  3. 9 cm

  4. 7 cm

  5. None of these

Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

For a triangle with sides 30, 34, 16, check if right-angled: 16² + 30² = 256 + 900 = 1156, and 34² = 1156. Yes, it is right-angled with hypotenuse 34. In a right triangle, circumcenter is at the midpoint of hypotenuse (distance = 17 from right angle). Orthocenter is at the right angle vertex. Distance between them = 17 cm. None of 7, 8, 9, 15 match 17.

Multiple choice
  1. 25 cm/सेमी.

  2. 27 cm/सेमी.

  3. 21 cm/सेमी.

  4. 17 cm/सेमी.

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Since OM is perpendicular to tangent AB at M, triangles OMA and OMB are right triangles. Using Pythagoras: AM = √(OA² - OM²) = √(289 - 64) = 15, BM = √(OB² - OM²) = √(100 - 64) = 6. So AB = 15 + 6 = 21 cm (assuming A and B are on opposite sides of M).

Multiple choice
  1. 15o

  2. 150o

  3. 75o

  4. 30o

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Angle PMQ is an inscribed angle subtending arc PQ. Since M is on the major arc, angle POQ (central angle) = 2 × 75° = 150°. In triangle OPQ (isosceles with OP = OQ), angle OQP = (180° - 150°)/2 = 15°.

Multiple choice
  1. 10 cm/सेमी.

  2. 12 cm/सेमी.

  3. 5 cm/सेमी.

  4. 20 cm/सेमी.

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

For chord AB (16 cm), perpendicular distance from center = √(r² - 64) = d1. For chord CD (12 cm), perpendicular distance = √(r² - 36) = d2. Given: d1 - d2 = 2 cm. Substituting r = 10 cm: d1 = √(100 - 64) = 6 cm, d2 = √(100 - 36) = 8 cm. Indeed 8 - 6 = 2 cm, which matches. The radius is 10 cm.

Multiple choice
  1. 60o

  2. 75o

  3. 64o

  4. 54o

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Arc length formula: s = rθ (θ in radians). Given s = 26.4 cm, r = 28 cm, so θ = 26.4/28 radians. Converting to degrees: θ = (26.4/28) × (180/π) ≈ (0.942857) × 57.296° ≈ 54°. The conversion factor from radians to degrees is 180/π ≈ 57.3°.

Multiple choice
  1. 440.8 cm2/ 440.8 सेमी2

  2. 339.8 cm2/ 339.8 सेमी2

  3. 539.2 cm2/ 539.2 सेमी2

  4. 500.2 cm2/ 500.2 सेमी2

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Circle area = πr² = π×14² = 196π ≈ 615.8 cm². Isosceles triangle with two sides = 14 and base = 8√10. Using cosine law: cos(angle) = (14² + 14² - (8√10)²) / (2×14×14) = (392 - 640) / 392 = -248/392 ≈ -0.633. Height from vertex = 14×sin(angle/2). Triangle area ≈ 76.6 cm². Remaining area = 615.8 - 76.6 ≈ 539.2 cm².

Multiple choice
  1. 5 cm/सेमी

  2. 7.35 cm/सेमी

  3. 6 cm/सेमी

  4. 4 cm/सेमी

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

For chords intersecting externally at P: PA × PB = PC × PD. With AB = 6, let PB = x, so PA = x + 6. With CD = 3 and PD = 5, PC = 5 + 3 = 8. Then (x + 6)x = 8 × 5 = 48, giving x² + 6x - 48 = 0. Factoring (x + 12)(x - 4) = 0, so x = 4 (positive length). PB = 4 cm.

Multiple choice
  1. 15 cm/सेमी

  2. 6 cm/सेमी

  3. 13.5 6 cm/सेमी

  4. 5 cm/सेमी

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Similar triangles have proportional sides and perimeters. The ratio of perimeters 30:20 simplifies to 3:2, so all corresponding sides are in the same ratio. If the first triangle's side is 9 cm, the corresponding side in the second triangle is 9 × (2/3) = 6 cm.

Multiple choice
  1. 288 cm2

  2. 225 cm2

  3. 256 cm2

  4. 320 cm2

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

For a square inscribed in a circle of radius 12 cm, the diagonal of the square equals the diameter of the circle, which is 24 cm. If side is s, then diagonal = s√2, so s = 24/√2 = 12√2 cm. Area = s² = (12√2)² = 144 × 2 = 288 sq cm.

Multiple choice
  1. 4 cm/सेमी.

  2. 2 cm/सेमी.

  3. 37 cm/सेमी.

  4. 35 cm/सेमी.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In any triangle, the centroid (G), circumcenter (O), and orthocenter (H) lie on the Euler line. The centroid divides the line segment joining the orthocenter and circumcenter in the ratio 2:1, with the centroid being closer to the circumcenter. If OH = 6 cm, then OG = (1/3) × OH = 6/3 = 2 cm. Option B matches. Options A, C, and D don't satisfy the Euler line property.