Answer:
By comparing the ratios of sides in similar triangles ΔABC and ΔADB,we can say that 
Step-by-step explanation:
Given that ∠ABC=∠ADC, AD=p and DC=q.
Let us take compare Δ ABC and Δ ADB in the attached file , ∠A is common in both triangles
and given ∠ABC=∠ADB=90°
Hence using AA postulate, ΔABC ≈ ΔADB.
Now we will equate respective side ratios in both triangles.

Since we don't know BD , BC let us take first equality and plugin the variables given in respective sides.

Cross multiply

Hence proved.
Thanks this came in handy bc I'm a beginner
Step-by-step explanation:
<B is the right angle
<A is acute
<C is acute
<D is obtuse
Yes
hope this is understandably sure right easy for you