Question

Sorry for the weird marks but please help!!​

Answer 1

Answer:

C. 8 is the correct answer.

Step-by-step explanation:

Let <DAB be x°

Now,

taking x as reference angle in triangle ADB,

cosx = b/h

or, cosx = 4/AB

Now,

again taking x as reference angle in triangle ACB,

cosx = b/h

or, cosx = AB/20

Now,

cosx = AB/20 = 4/AB

or, AB/20 = 4/AB

or, AB² = 80

Now,

Using pythagoras theorem in triangle ABD,

h² = p² + b²

or, AB² = BD² + AD²

or, 80 = BD² + 4²

or, 80 - 16 = BD²

so, BD² = 64

so, BD = 8

Answer 2

Answer:

the answer is 4√7

Step-by-step explanation:

Using Pythagoras Thereon

It is 16²+ 4²

= 256+16

= √272

= √16.49

= 4√7