Triangle ABC is an isosceles triangle with AB=AC, side BA is produced to D such that AB=AD. Prove that angle BCD is a right angle.

In triangle ABC

AB=AC  so,angle ABC=angleACB

again since AC=AD

Therefore angleACD=angleADC

Now let angleABC=angleACB=x and angleACD=angleADC=y

so, ABC+BCD+BDC=180

>x+x+y+y=180

>2[x+y]=180

>x+y=90

>BCD=90

Therefore angle BCD is a right angle

  • 78
M A T H S = Meri Atma Tughe Hamesha Sataygi
  • -7
hmm
  • -15
Heeeheeeheee nice joke sanskar ;-)
  • -22
Seeing the picture :- Hoping that it will help u

  • 17
This is the solution for question if AB||CD.prove that p+q-r=180°

  • -2
Gooooogle it
  • -4
Please find this answer

  • 2
yeah chat ke liye nhi ha
  • -3
angle bcd = angle acb + angle acd
Now, angle acb = angle abc and angle acd = angle adc (Isosceles triangle)
angle bcd = angle abc + angle adc
angle bcd = 180 - angle bcd          ( Angle sum property)
angle bcd * 2 = 180
angle bcd = 90
Hence proved.
  
Cheers*
  • 2
hi
  • 1
In the figure angle AOC and angleBOC form a linear pair . If a-2b=30degree find 'a' and 'b'
  • 0
Please find this answer

  • 0
Answer : Given: AB = AC and AD = AB To Prove: ∠ BCD is a right angle Proof: In AB = AC (Given) ∠ACB = ∠ABC (Angles opposite to equal sides are equal) In AD = AB (Given) ∠ADC = ∠ACD (Angles opposite to equal sides are equal) Now, In ∠CAB + ∠ACB + ∠ABC = 180o ( Sum of interior angles of a triangle) ∠CAB + 2 ∠ACB = 180o (∠ACB = ∠ABC) ∠CAB = 180o - 2 ∠ACB (i) Similarly, In ∠CAD = 180o - 2 ∠ACD (ii) Also, ∠CAB + ∠CAD = 180o (BD is a straight line) Adding (i) and (ii), we get ∠CAB + ∠CAD = 180o - 2∠ACB + 180o - 2∠ACD 180o = 360o - 2∠ACB - 2∠ACD 2 (∠ACB + ∠ACD) = 180o ∠BCD = 90o Hence, Proved
  • 0
please and answer
  • 0
Please find this answer

  • 0
Please find this answer

  • 0
I don't know about this question
  • 0
It is not clear
  • 0
Please find this answer

  • 0
class 8 ka Hamari Duniya Pehla chapter ka question answer
  • 0
In Fig 16.6, if x+y=w+z, then prove that AOB is a line
  • 0
Hiii
  • 0
The suplement angle of 78? is
  • 0
Angle sum property of triangle activity
  • 0
Geography 11th class
  • 0
Kaha tumko nahi pata hai jo dusro ko parashan karta ho
  • 0
What are you looking for?