Advertisements
Advertisements
Question
If perpendiculars from any point within an angle on its arms are congruent, prove that it lies on the bisector of that angle.
Advertisements
Solution
Given that, if perpendicular from any point within, an angle on its arms is congruent, prove that it lies on the bisector of that angle
Now,
Let us consider an angle ABC and let BP be one of the arm within the angle
Draw perpendicular PN and PM on the arms BC and BA such that they meet BC and BA in N and M respectively.
Now, in ΔBPM and ΔBPN
We have ∠BMP= BNP = 90° [given]
BP=BP [Common side]
And MP=NP [given]
So, by RHS congruence criterion, we have
ΔBPM≅ΔBPN
Now,
∠MBP=∠NBP [ Corresponding parts of congruent triangles are equal]
⇒ BP is the angular bisector of ∠ABC
∴ Hence proved

APPEARS IN
RELATED QUESTIONS
l and m are two parallel lines intersected by another pair of parallel lines p and q (see the given figure). Show that ΔABC ≅ ΔCDA.

In Fig. 10.40, it is given that RT = TS, ∠1 = 2∠2 and ∠4 = 2∠3. Prove that ΔRBT ≅ ΔSAT.
In Fig. 10.92, it is given that AB = CD and AD = BC. Prove that ΔADC ≅ ΔCBA.
In Δ ABC, ∠B = 35°, ∠C = 65° and the bisector of ∠BAC meets BC in P. Arrange AP, BP and CP in descending order.
A triangle ABC has ∠B = ∠C.
Prove that: The perpendiculars from B and C to the opposite sides are equal.
From the given diagram, in which ABCD is a parallelogram, ABL is a line segment and E is mid-point of BC.
prove that : AL = 2DC
In the following diagram, ABCD is a square and APB is an equilateral triangle.

- Prove that: ΔAPD ≅ ΔBPC
- Find the angles of ΔDPC.
In the following diagram, AP and BQ are equal and parallel to each other. 
Prove that: AB and PQ bisect each other.
In quadrilateral ABCD, AD = BC and BD = CA.
Prove that:
(i) ∠ADB = ∠BCA
(ii) ∠DAB = ∠CBA
ABC is a right triangle with AB = AC. Bisector of ∠A meets BC at D. Prove that BC = 2AD.
