Triangle 75

Triangle ABC has angle C bisected and intersected AB at D. Angle A measures 20 degrees, and angle B measures 40 degrees. The question is to determine AB-AC if length AD=1.

Correct answer:

x =  0.3949

Step-by-step explanation:

AD=1 A=20  B=40   C=180AB=1802040=120  ACD=C/2=120/2=60  DCB=C/2=120/2=60   ADC=180AACD=1802060=100  CDB=180BDCB=1804060=80    sin ACD sin ADC = AC : AD  AC=AD sinACDsinADC=AD sin60° sin100° =1 sin60° sin100° =1 0.8660250.984808=1.13716  DC=AD sinACDsinA=AD sin60° sin20° =1 sin60° sin20° =1 0.8660250.34202=0.39493  DB=DC sinBsinDCB=DC sin40° sin60° =0.3949 sin40° sin60° =0.3949 0.6427880.866025=0.53209  AB=AD+DB=1+0.53211.5321  x=ABAC=1.53211.1372=0.3949

Did you find an error or inaccuracy? Feel free to write us. Thank you!

Tips for related online calculators
Need help calculating sum, simplifying, or multiplying fractions? Try our fraction calculator.
Cosine rule uses trigonometric SAS triangle calculator.
See also our trigonometric triangle calculator.
Try conversion angle units angle degrees, minutes, seconds, radians, grads.

You need to know the following knowledge to solve this word math problem:

We encourage you to watch this tutorial video on this math problem: video1   video2

Related math problems and questions: