Advertisements
Advertisements
प्रश्न
If the perpendicular bisector of the sides of a triangle PQR meet at I, then prove that the line joining from P, Q, R to I are equal.
Advertisements
उत्तर
Given:
In ΔPQR,
PA is the perpendicular bisector of QR ⇒ QA = RA
RC is the perpendicular bisector of PQ ⇒ PC = QC
QB is the perpendicular bisector of PR ⇒ PR = RB
PA, RC and QB meet at I.
To prove: IP = IQ = IR
Proof:
In ΔQIA and ΔRIA
QA = RA ....[Given]
∠QAI = ∠RAI ....[Each = 90]
IA = IA ....[Common]
∴ By Side-Angle-Side criterion of congruence,
ΔIQ = IR ....(i)
Similarly, in ΔRIB and ΔPIB
RB = PB ...[Given]
∠RBI = ∠PBI ...[Each = 90°]
IB = IB ...[Common]
∴ By Side-Angle-Side criterion of congruence,
ΔRIB ≅ ΔPIB
The corresponding parts of the congruent triangles are congruent.
∴ IR = IP ....(ii)
From (i) and (ii), we have
IP = IQ = IR.
APPEARS IN
संबंधित प्रश्न
If ΔDEF ≅ ΔBCA, write the part(s) of ΔBCA that correspond to `bar(DF)`
In a ΔABC, if AB = AC and ∠B = 70°, find ∠A.
Mark the correct alternative in each of the following:
If ABC ≅ ΔLKM, then side of ΔLKM equal to side AC of ΔABC is
If ΔABC ≅ ΔABC is isosceles with
Observe the information shown in pair of triangle given below. State the test by which the two triangles are congruent. Write the remaining congruent parts of the triangles.

From the information shown in the figure,
in ΔPTQ and ΔSTR
seg PT ≅ seg ST
∠PTQ ≅ ∠STR ...[Vertically opposite angles]
∴ ΔPTQ ≅ ΔSTR ...`square` test
∴ `{:("∠TPQ" ≅ square),("and" square ≅ "∠TRS"):}}` ...corresponding angles of congruent triangles
seg PQ ≅ `square` ...corresponding sides of congruent triangles
In the pair of triangles given below, the parts shown by identical marks are congruent. State the test and the one-to-one correspondence of vertices by which the triangles in the pair are congruent, the remaining congruent parts.

The following figure has shown a triangle ABC in which AB = AC. M is a point on AB and N is a point on AC such that BM = CN.
Prove that: (i) AM = AN (ii) ΔAMC ≅ ΔANB

Sides, AB, BC and the median AD of ΔABC are equal to the two sides PQ, QR and the median PM of ΔPQR. Prove that ΔABC ≅ ΔPQR.

In ΔABC, AD is a median. The perpendiculars from B and C meet the line AD produced at X and Y. Prove that BX = CY.
The congruent figures super impose each other completely.
