Answer:


Step-by-step explanation:
Given: See Attachment
Required
Determine the length of the legs
To do this, we apply Pythagoras theorem.

In this case:

Open Bracket



Collect Like Terms


Solving using quadratic formula:

So:
or 
Since, x can't be negative, then:

One of the leg is:






First, subtract 2/3 from both sides and you get

Then multiply both sides by 6/5 and you get
Bring them to the same denominator and solve for x
21 + 28 = 49 students
Ration of history 21 to students 49 = d)21:49