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In right-angled ΔABC, BD ⊥ AC. If AD= 4, DC= 9, then find BD.
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The perpendicular height of a cone is 12 cm and its slant height is 13 cm. Find the radius of the base of the cone.
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A circle is inscribed in square ABCD of side 14 cm. Complete the following activity to find the area of the shaded portion.
Activity:
Area of square ABCD = ______
= 142
= 196 cm2
Area of circle = πr2 = `22/7xx 7^2`
= ____ cm2
Area of shaded portion = Area of square ABCD – Area of circle
= 196 – _______
= _____ cm2
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In the given figure, M is the centre of the circle and seg KL is a tangent segment. L is a point of contact. If MK = 12, KL = `6sqrt3`, then find the radius of the circle.
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Prove the following theorem:
Tangent segments drawn from an external point to the circle are congruent.
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In the given figure `square`ABCD is a square of side 50 m. Points P, Q, R, S are midpoints of side AB, side BC, side CD, side AD respectively. Find area of shaded region
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As shown in figure, ∠DFE = 90°, FG ⊥ ED, If GD = 8, FG = 12, then (1) EG = ? (2) FD = ? (3) EF = ?

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Segment DP and segment DQ are tangent segments to the circle with center A. If DP = 7 cm. So find the length of the segment DQ?

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The chords corresponding to congruent arcs of a circle are congruent. Prove the theorem by completing following activity.

Given: In a circle with centre B
arc APC ≅ arc DQE
To Prove: Chord AC ≅ chord DE
Proof: In ΔABC and ΔDBE,
side AB ≅ side DB ...`square`
side BC ≅ side `square` ...`square`
∠ABC ≅ ∠DBE ...[Measure of congruent arcs]
∆ABC ≅ ∆DBE ...`square`
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Length of a tangent segment drawn from a point which is at a distance 15 cm from the centre of a circle is 12 cm, find the diameter of the circle?
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Tangent segments drawn from an external point to a circle are congruent, prove this theorem. Complete the following activity.

Given: `square`
To Prove: `square`
Proof: Draw radius AP and radius AQ and complete the following proof of the theorem.
In ∆PAD and ∆QAD,
seg PA ≅ `square` ...[Radii of the same circle]
seg AD ≅ seg AD ...[`square`]
∠APD ≅ ∠AQD = 90° ...[Tangent theorem]
∴ ∆PAD ≅ ∆QAD ...[`square`]
∴ seg DP ≅ seg DQ ...[`square`]
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In the adjoining figure, O is the center of the circle. From point R, seg RM and seg RN are tangent segments touching the circle at M and N. If (OR) = 10 cm and radius of the circle = 5 cm, then
- What is the length of each tangent segment?
- What is the measure of ∠MRO?
- What is the measure of ∠MRN?

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In the adjoining figure circle with Centre, Q touches the sides of ∠MPN at M and N. If ∠MPN = 40°, find measure of ∠MQN.

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The figure ΔABC is an isosceles triangle with a perimeter of 44 cm. The sides AB and BC are congruent and the length of the base AC is 12 cm. If a circle touches all three sides as shown in the figure, then find the length of the tangent segment drawn to the circle from the point B.

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If AB and CD are the common tangents in the circles of two unequal (different) radii, then show that seg AB ≅ seg CD.

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Seg RM and seg RN are tangent segments of a circle with centre O. Prove that seg OR bisects ∠MRN as well as ∠MON with the help of activity.

Proof: In ∆RMO and ∆RNO,
∠RMO ≅ ∠RNO = 90° ...[`square`]
hypt OR ≅ hypt OR ...[`square`]
seg OM ≅ seg `square` ...[Radii of the same circle]
∴ ∆RMO ≅ ∆RNO ...[`square`]
∠MOR ≅ ∠NOR
Similairy ∠MRO ≅ `square` ...[`square`]
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Prove that, tangent segments drawn from an external point to the circle are congruent.
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If x = `θ/360` × 2πr then what is x in the formula?
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In the given figure, a rectangle ABCD is inscribed inside a semi-circle of radius 10 cm. Using the dimensions given in the figure, determine the area of the shaded region.

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In a parallelogram ABCD, ∠B = 105°. Determine the measure of ∠A and ∠D.
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