Isosceles triangle with angle bisector

  • Thread starter Frank212
  • Start date
  • #1
14
1

Homework Statement


Find x[/B]
bandicam 2016-08-12 23-30-16-190.jpg


Homework Equations


a+b+c=180[/B]


The Attempt at a Solution


ADB= 65+65+50=180
How do I find x in DBC?
 

Answers and Replies

  • #2
SammyS
Staff Emeritus
Science Advisor
Homework Helper
Gold Member
11,377
1,038

Homework Statement


Find x[/B]
View attachment 104594

Homework Equations


a+b+c=180[/B]


The Attempt at a Solution


ADB= 65+65+50=180
How do I find x in DBC?
What is the measure of angle CBD ?
 
  • #3
14
1
What is the measure of angle CBD ?
What is the measure of angle CBD ?

ADB=50+65+65=180
angle bisector -> angle on a line 180 degrees. 180-65=115
x= 180-115=65, 65/2=32.5
CBD=32.5+115+32.5

x=32.5
 
  • #4
SammyS
Staff Emeritus
Science Advisor
Homework Helper
Gold Member
11,377
1,038
ADB=50+65+65=180
angle bisector -> angle on a line 180 degrees. 180-65=115
x= 180-115=65, 65/2=32.5
CBD=32.5+115+32.5

x=32.5
Actually, I asked about angle CBD, ( ∠ CBD ), not triangle CBD ( Δ CBD ).

Maybe, that's what you mean by
" angle bisector -> angle on a line 180 degrees. 180-65=115 ",​
but an angle bisector cuts an angle exactly into two angle of equal measure.

So, yes, .∠ CBD = 180° - 65° = 115° .

It's really very confusing, and incorrect, when you state the following.
CBD=32.5+115+32.5
 

Related Threads on Isosceles triangle with angle bisector

  • Last Post
Replies
7
Views
917
  • Last Post
Replies
4
Views
8K
  • Last Post
Replies
3
Views
684
  • Last Post
2
Replies
27
Views
4K
  • Last Post
Replies
1
Views
3K
  • Last Post
Replies
2
Views
1K
  • Last Post
Replies
4
Views
2K
  • Last Post
Replies
10
Views
2K
  • Last Post
Replies
6
Views
303
Replies
14
Views
8K
Top