Advertisements
Advertisements
प्रश्न
Two lines AB and CD intersect at O such that BC is equal and parallel to AD. Prove that the lines AB and CD bisect at O.
Advertisements
उत्तर
It is given that
BC = AD
BC || AD

We have to prove that AB and CD bisect at O.
If we prove that ΔAOD ≅ ΔBOC , then
We can prove AB and CDbisects atO.
Now in ΔAOD and ΔBOC
AD = BC(Given)
∠OBC =∠OAD (Since AD || BC and AB is transversal)
And ∠OCB = ∠ODA(since AD || BC and CD is transversal)
So by ASAcongruence criterion we have,
ΔAOD ≅ ΔBOC, so
OA = OB
OD = OC
Hence ABand CD bisect each other at O.
APPEARS IN
संबंधित प्रश्न
In Figure AB = AC and ∠ACD =105°, find ∠BAC.

Find the measure of each exterior angle of an equilateral triangle.
In a ΔABC, if AB = AC and ∠B = 70°, find ∠A.
P is a point on the bisector of an angle ∠ABC. If the line through P parallel to AB meets BC at Q, prove that triangle BPQ is isosceles.
Angles A, B, C of a triangle ABC are equal to each other. Prove that ΔABC is equilateral.
Which of the following statements are true (T) and which are false (F):
Sides opposite to equal angles of a triangle may be unequal
Which of the following statements are true (T) and which are false (F):
If the bisector of the vertical angle of a triangle bisects the base, then the triangle may be isosceles.
Which of the following statements are true (T) and which are false (F)?
Sum of any two sides of a triangle is greater than twice the median drawn to the third side.
Fill in the blank to make the following statement true.
In a right triangle the hypotenuse is the .... side.
Fill in the blank to make the following statement true.
If two angles of a triangle are unequal, then the smaller angle has the........ side opposite to it.
ABC is a triangle. The bisector of the exterior angle at B and the bisector of ∠C intersect each other at D. Prove that ∠D = \[\frac{1}{2}\] ∠A.
In a triangle ABC, if AB = AC and AB is produced to D such that BD = BC, find ∠ACD: ∠ADC.
In the given figure, what is z in terms of x and y?

In the given figure, for which value of x is l1 || l2?

In the given figure, what is y in terms of x?

The side BC of ΔABC is produced to a point D. The bisector of ∠A meets side BC in L. If ∠ABC = 30° and ∠ACD = 115°, then ∠ALC = ______.
D is a point on the side BC of a ∆ABC such that AD bisects ∠BAC. Then ______.
AD is a median of the triangle ABC. Is it true that AB + BC + CA > 2AD? Give reason for your answer.
Show that in a quadrilateral ABCD, AB + BC + CD + DA < 2(BD + AC)
