Given: ABCD is a trapezoid, AB = CD,

BK ⊥ AD (they are perpendicular
, AK = 10, KD = 20
Find: BC AD

I got that BC is 15 and AD is 35
so I got BC/AD=15/35

is this answer right?

and is so can you add the answer and an explanation

1 answer

AD is 30. (Add AK and KD, both given)
Since AB = CD, this is an isosceles trapezoid.
Thus we have symmetry:
Given that BK is perp. To AD with AK = 10
We can draw CL perp to AD; and by symmetry, LD will also be 10.
This leaves KL as 10 ( given that KD is 20).
Thus BC is 10.

BC/AD = 10/30 = 1/3