Answer
the correct answer should be 109
Step-by-step explanation:
Answer:

Step-by-step explanation:
Given:
The above triangle
Required
Solve for AB in terms of a, b and angle C
Considering right angled triangle BOC where O is the point between b-x and x
From BOC, we have that:

Make h the subject:

Also, in BOC (Using Pythagoras)

Make
the subject

Substitute
for h
becomes


Factorize

In trigonometry:

So, we have that:

Take square roots of both sides

In triangle BOA, applying Pythagoras theorem, we have that:

Open bracket

Substitute
and
in 


Open Bracket

Reorder

Factorize:

In trigonometry:

So, we have that:


Take square roots of both sides

First one and the last one are rational. And the other two of them are irrational.
Answer:
4
Step-by-step explanation:
y inversely proportional to x
y=1k/x
4=k/4
k=4×4
k=16
to find y
y=16/4
y=4
Sender would be 4 x 7 divided by 15