# Thread: figure out isosceles triangles angles

1. ## figure out isosceles triangles angles

In isosceles triangle abc, angle A =40 , AD is median, and CM and BP are leg altitudes.
I figured that angles B and C are 70, M and P would be 70 and D is 90. Is this right and where do I go from here?

2. Originally Posted by sanee66

In isosceles triangle abc, angle A =40 , AD is median, and CM and BP are leg altitudes.
I figured that angles B and C are 70, M and P would be 70 and D is 90. Is this right and where do I go from here?
Hello,

I assume that the the lower case letters indicate the angles and that you want to know the values of these angles. Right?

1. $\angle{a} = \angle{b} = 20^\circ$ Symmetry property
2. $\angle{d} = 20^\circ$ Use the right triangle BCP to calculate the angle.
3. $\angle{d} = \angle{f} = 20^\circ$ Symmetry property
4. $\angle{c} = \angle{e} = 50^\circ$ Use the result of 3.: You already know that c + d = 70° and you know the angle d
5. $\angle{m} = \angle{n} = 40^\circ$