Posted by Anonymous on Thursday, March 7, 2013 at 1:57pm.
Since AD=DB, triangle ABD is isosceles, so
∠DAB = ∠DBA = 75° and ∠ADB = 30°
Now draw AC, and again we have isosceles triangles ABC and BCD.
∠BCD = 75°
Related Questions
Geometry - ABCD is a convex quadrilateral satisfying AB=BC=CD, AD=DB and \angle ...
geometry! - ABC is an isosceles triangle with AB=AC, ∠BAC=96∘...
maths - ABCD is a convex cyclic quadrilateral such that AB=AD and ∠BAD...
maths - ABCD is a convex cyclic quadrilateral such that AB=AD and ∠BAD...
geometry - ABCD is a rectangle. On line segment AB, E is a point such that &...
geoMETRY! - ABC is an acute angle triangle with points D and E on BC and AC, ...
geometry! - ABC is an acute angle triangle with points D and E on BC and AC, ...
geometry - If m∠BCD = 60 and m∠DEC = 80, what is the measure...
geometry - If m∠BCD = 60 and m∠DEC = 80, what is the measure...
math - If m∠BCD = 70 and m∠DEC = 56, what is the measure of...
For Further Reading