We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive pseudonymised information about your use of our website. cookie policy and privacy policy.
 
+0  
 
+1
258
2
avatar+1432 

In the figure, BA = AD = DC and point D is on segment BC. The measure of angle ACD is 22.5 degrees. What is the measure of angle ABC?

 

Thanks! ^^

 Feb 24, 2018

Best Answer 

 #1
avatar+18057 
+1

If BA = AD   then by the law of sin s     AngleABC = Angle ADB   

If  AD = DC                 then   Angle DAC = Angle DCA  = 22.5

A triangle has 180 degrees in it   so  angle ADC = 180 - 2(22.5) = 135 degrees

 

Angle ADC + ADB = 180 degrees (a straight line)  

   ADB = 180 - ADC = 180 - 135 = 45 degrees

 

Now see the red above?   ADB = ABC = 45 degrees

 Feb 24, 2018
 #1
avatar+18057 
+1
Best Answer

If BA = AD   then by the law of sin s     AngleABC = Angle ADB   

If  AD = DC                 then   Angle DAC = Angle DCA  = 22.5

A triangle has 180 degrees in it   so  angle ADC = 180 - 2(22.5) = 135 degrees

 

Angle ADC + ADB = 180 degrees (a straight line)  

   ADB = 180 - ADC = 180 - 135 = 45 degrees

 

Now see the red above?   ADB = ABC = 45 degrees

ElectricPavlov Feb 24, 2018
 #2
avatar+1432 
+2

Thank you so much!

AnonymousConfusedGuy  Feb 24, 2018

25 Online Users

avatar
avatar