+0  
 
0
810
4
avatar+218 

Hey, I need some help with this geometry question that I'm stuck on. Thanks!

 

Image:

 

 Sep 15, 2019
 #1
avatar+2862 
+2

I will give only hints as this problem only requires basic addition and subtraction

 

The sum of the angles of Triangle ABC add up to 180

 

Line segment DBC is 180 degrees, and if DBA is 124, then what must be ABC?

 Sep 15, 2019
 #2
avatar+128079 
+1

This uses the Exterior Angle Theorem

 

It says that

 

measure of DBA  = measure of BAC + measure of  ACB

 

124  = 95  + measure of ACB    subtract 95 from both sides

 

29°  =   measure of ACB

 

 

cool cool cool

 Sep 15, 2019
edited by CPhill  Sep 15, 2019
 #4
avatar
0

 

Chris, DBA is 124o  not  125o 

Guest Sep 15, 2019
 #3
avatar
0

 

A straight line is 180o so 180o – 124o  =  56o  =  angle ABC 

 

A triangle contains 180o and so add ABC + BAC to see how much you need left over for BCA  

 

ABC + BAC  =  56o + 95o  =  151o   

 

Since the whole triangle contains 180o then BCA has to be 180o – 151o  =  29o 

.

 Sep 15, 2019

10 Online Users

avatar
avatar
avatar
avatar
avatar
avatar
avatar