2
$\begingroup$

In $\triangle{ABC}$, given $\angle{A}=80^\circ$, $\angle{B}=\angle{C}=50^\circ$, D is a point in $\triangle{ABC}$, which $\angle{DBC}=20^\circ,\angle{DCB}=40^\circ$. Then how to find find $\angle{DAC}$?

thanks.

  • 0
    I wonder if this isn't the same kind of problem as http://math.stackexchange.com/questions/63819/determine-angle-x-using-only-elementary-geometry/63833#638332011-09-15
  • 0
    (didn't do a careful check, but...) possible duplicate of [Finding an angle within an 80-80-20 isosceles triangle](http://math.stackexchange.com/questions/6942/finding-an-angle-within-an-80-80-20-isosceles-triangle)2011-09-15

2 Answers 2