Geometry Questions

Multiple choice
  1. 5 cm

  2. 4 cm

  3. 4.5 cm

  4. 5.5 cm

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

Let O be the center, P the external point. OP = 13. Secant PAB, PA = 9, AB = 7, so PB = 16. Power of point P = PA * PB = 9 * 16 = 144. Also, Power = d^2 - r^2, where d=13. 144 = 13^2 - r^2 = 169 - r^2. r^2 = 169 - 144 = 25. r = 5.

Multiple choice
  1. 3 cm

  2. 4 cm

  3. 5 cm

  4. 6 cm

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

The tangent to a circle is perpendicular to the radius at the point of contact. This forms a right triangle with the radius (r), tangent (3 cm), and hypotenuse (5 cm). r^2 + 3^2 = 5^2, so r^2 = 25 - 9 = 16, r = 4 cm.

Multiple choice
  1. 12 cm

  2. 15 cm

  3. 13 cm

  4. 12.5 cm

  5. 17 cm

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

For an isosceles triangle with sides 20, 20, 24, the height h to the base 24 is sqrt(20^2 - 12^2) = sqrt(400 - 144) = sqrt(256) = 16. Area = 0.5 * base * height = 0.5 * 24 * 16 = 192. Circumradius R = (abc) / (4 * Area) = (20 * 20 * 24) / (4 * 192) = 9600 / 768 = 12.5.

Multiple choice
  1. an angle bisector

  2. a circle with diameter 4 cm and centre M

  3. a straight line

  4. a circle with radius 4 cm and centre M

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

The locus of points at a constant distance from a fixed point is the definition of a circle with that point as the center and the distance as the radius.

Multiple choice
  1. 14 cm

  2. 12 cm

  3. 10 cm

  4. 9 cm

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

Let the shortest leg be x. Hypotenuse = x + 6, longer leg = x + 3. By Pythagoras: x^2 + (x + 3)^2 = (x + 6)^2. Solving x^2 + x^2 + 6x + 9 = x^2 + 12x + 36 gives x^2 - 6x - 27 = 0. Factoring (x - 9)(x + 3) = 0, so x = 9.

Multiple choice
  1. 570 cm2

  2. 1968 cm2

  3. 616 cm2

  4. 4464 cm2

  5. None of these

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

A circle inscribed in a square has a diameter equal to the side of the square. Diameter = 28 cm, so radius = 14 cm. Area = pi * r^2 = (22/7) * 14 * 14 = 22 * 2 * 14 = 616 cm^2.