Question #f3da8 Geometry Angles and Intersecting Lines Angles with Triangles and Polygons 1 Answer CW Feb 16, 2017 #AD=1/3# Explanation: As shown in the diagram, #AE and CD# are the two altitudes. #DeltaBDC# is a right-angled triangle. Given #BE=6, EC=8, and BD=9#, #=> BC=BE+EC=6+8=14# Let #angleDBC=x# #cosx=(BD)/(BC)=9/14# #DeltaABE# is also a right triangle, right-angled at #E#, #=> ABcosx=6# #=> AB=6/cosx=6/(9/14)=6xx14/9=28/3# #AD=AB-BD=28/3-9=1/3# Answer link Related questions How do you classify the triangle given 2 cm, 2 cm, 2 cm? The angles of a triangle have the ratio 3:2:1. What is the measure of the smallest angle? Is an equilateral triangle is sometimes, never or always an isosceles triangle? What is an isosceles triangle? How do I prove that these are the vertices of an isosceles triangle: (-3,0), (0,4), (3,0)? Is it possible to have an isosceles scalene triangle? How would you show that a triangle with vertices (13,-2), (9,-8), (5,-2) is isosceles? An isosceles right triangle has legs that are each 4cm. What is the length of the hypotenuse? Triangle XYZ is isosceles. The base angles, angle X and angle Y, are four times the measure of... What is the isosceles triangle theorem? See all questions in Angles with Triangles and Polygons Impact of this question 1171 views around the world You can reuse this answer Creative Commons License