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In the given, seg BE ⊥ seg AB and seg BA ⊥ seg AD.
if BE = 6 and AD = 9 find `(A(Δ ABE))/(A(Δ BAD))`.

Concept: Properties of Ratios of Areas of Two Triangles
In the figure, ray YM is the bisector of ∠XYZ, where seg XY ≅ seg YZ, find the relation between XM and MZ.

Concept: Property of an Angle Bisector of a Triangle

In the above figure, line l || line m and line n is a transversal. Using the given information find the value of x.
Concept: Property of Three Parallel Lines and Their Transversals
Draw seg AB = 6.8 cm and draw perpendicular bisector of it.
Concept: Property of an Angle Bisector of a Triangle

In the above figure, line AB || line CD || line EF, line l, and line m are its transversals. If AC = 6, CE = 9. BD = 8, then complete the following activity to find DF.
Activity :
`"AC"/"" = ""/"DF"` (Property of three parallel lines and their transversal)
∴ `6/9 = ""/"DF"`
∴ `"DF" = "___"`
Concept: Property of Three Parallel Lines and Their Transversals
In the following figure, ray PT is the bisector of ∠QPR Find the value of x and perimeter of ∠QPR.

Concept: Property of an Angle Bisector of a Triangle
A roller of diameter 0.9 m and the length 1.8 m is used to press the ground. Find the area of the ground pressed by it in 500 revolutions.
`(pi=3.14)`
Concept: Properties of Ratios of Areas of Two Triangles
Draw the circumcircle of ΔPMT in which PM = 5.6 cm, ∠P = 60°, ∠M = 70°.
Concept: Property of an Angle Bisector of a Triangle
In ΔABC, B − D − C and BD = 7, BC = 20, then find the following ratio.

(i) `"A(ΔABD)"/"A(ΔADC)"`
(ii) `"A(ΔABD)"/"A(ΔABC)"`
(iii) `"A(ΔADC)"/"A(ΔABC)"`
Concept: Properties of Ratios of Areas of Two Triangles
Prove that, The areas of two triangles with the same height are in proportion to their corresponding bases. To prove this theorem start as follows:
- Draw two triangles, give the names of all points, and show heights.
- Write 'Given' and 'To prove' from the figure drawn.
Concept: Properties of Ratios of Areas of Two Triangles
From the information given in the figure, determine whether MP is the bisector of ∠KMN.

Concept: Property of an Angle Bisector of a Triangle
If ΔABC ∼ ΔDEF such that ∠A = 92° and ∠B = 40°, then ∠F = ?

Concept: Property of an Angle Bisector of a Triangle
If ΔABC ∼ ΔDEF, length of side AB is 9 cm and length of side DE is 12 cm, then find the ratio of their corresponding areas.
Concept: Properties of Ratios of Areas of Two Triangles
In the figure, PQ ⊥ BC, AD ⊥ BC. To find the ratio of A(ΔPQB) and A(ΔPBC), complete the following activity.

Given: PQ ⊥ BC, AD ⊥ BC
Now, A(ΔPQB) = `1/2 xx square xx square`
A(ΔPBC) = `1/2 xx square xx square`
Therefore,
`(A(ΔPQB))/(A(ΔPBC)) = (1/2 xx square xx square)/(1/2 xx square xx square)`
= `square/square`
Concept: Properties of Ratios of Areas of Two Triangles

In ∆PQR seg PM is a median. Angle bisectors of ∠PMQ and ∠PMR intersect side PQ and side PR in points X and Y respectively. Prove that XY || QR.
Complete the proof by filling in the boxes.
solution:
In ∆PMQ,
Ray MX is the bisector of ∠PMQ.
∴ `("MP")/("MQ") = square/square` .............(I) [Theorem of angle bisector]
Similarly, in ∆PMR, Ray MY is the bisector of ∠PMR.
∴ `("MP")/("MR") = square/square` .............(II) [Theorem of angle bisector]
But `("MP")/("MQ") = ("MP")/("MR")` .............(III) [As M is the midpoint of QR.]
Hence MQ = MR
∴ `("PX")/square = square/("YR")` .............[From (I), (II) and (III)]
∴ XY || QR .............[Converse of basic proportionality theorem]
Concept: Property of an Angle Bisector of a Triangle

In ΔABC, ray BD bisects ∠ABC, A – D – C, seg DE || side BC, A – E – B, then for showing `("AB")/("BC") = ("AE")/("EB")`, complete the following activity:
Proof :
In ΔABC, ray BD bisects ∠B.
∴ `square/("BC") = ("AD")/("DC")` ...(I) (`square`)
ΔABC, DE || BC
∴ `(square)/("EB") = ("AD")/("DC")` ...(II) (`square`)
∴ `("AB")/square = square/("EB")` ...[from (I) and (II)]
Concept: Property of an Angle Bisector of a Triangle
In the following figure, in ΔABC, ∠B = 90°, ∠C = 60°, ∠A = 30°, AC = 18 cm. Find BC.

Concept: Property of 30°- 60°- 90° Triangle Theorem
Adjacent sides of a parallelogram are 11 cm and 17 cm. If the length of one of its diagonal is 26 cm, find the length of the other.
Concept: Apollonius Theorem
In the following figure, AE = EF = AF = BE = CF = a, AT ⊥ BC. Show that AB = AC = `sqrt3xxa`

Concept: Similarity in Right Angled Triangles
If the sides of a triangle are 6 cm, 8 cm and 10 cm, respectively, then determine whether the triangle is a right angle triangle or not.
Concept: Right-angled Triangles and Pythagoras Property
