In the figure AB BC and DB BE A x degree C 4y degree D
     In the figure, AB = BC and DB = BE, A = x degree, C = 4y degree, D = 4x - 5 degree and  E = 15 y degree.  (a) How are the triangles related?  (b) Find x, y, A, C, D and  E.   
  
  Solution
Solution:
(a)
In triangle ABE and triangle CBD
angle < ABE = angle < CDB ( vertically opposite angle)
BE = BD ( Given)
AB = CB ( Given)
therefore trinagle ABE and triangle CDB are congruents to each other by SAS
(b)
In both triangle
<A = <C
x = 4y
Now in both trinagle trinagle
x+15y +<B = 180 = 4x-5+4y +<B
x+15y = 4x+4y -5
3x -11y =5
as we know that 4x = y
12y -11y = 5
y= 5 and x = 20
<A = 20 , <C = 20 , <D = 75 and E = 75

