Answer:
1) AD=BC(corresponding parts of congruent triangles)
2)The value of x and y are 65 ° and 77.5° respectively
Step-by-step explanation:
1)
Given : AD||BC
AC bisects BD
So, AE=EC and BE=ED
We need to prove AD = BC
In ΔAED and ΔBEC
AE=EC (Given)
( Vertically opposite angles)
BE=ED (Given)
So, ΔAED ≅ ΔBEC (By SAS)
So, AD=BC(corresponding parts of congruent triangles)
Hence Proved
2)
Refer the attached figure

In ΔDBC
BC=DC (Given)
So,
(Opposite angles of equal sides are equal)
So,
So,
(Angle sum property)
x+x+50=180
2x+50=180
2x=130
x=65
So,
Now,

So,
In ΔABD
AB = BD (Given)
So,
(Opposite angles of equal sides are equal)
So,
So,
(Angle Sum property)
y+y+25=180
2y=180-25
2y=155
y=77.5
So, The value of x and y are 65 ° and 77.5° respectively
Answer:
y=-4+-1
Step-by-step explanation:
hope this is what your looking for
All of the telephones * all of the telephones minus one (because one is in use)
85 * 84 = 7140 connections
Answer: A
Step-by-step explanation: you have to use the 2 points distance formula that is ✓(xb - xa)^2 + (yb - ya)^2 so ✓(6+6)^2 + (-3-4)^2 = ✓144 + 49 = ✓193
4r - 8 = 5r + 12
4r - 5r = 12 + 8
-r = 20
r = -20 <===