How did the knights Templar become a banking establishment?

The Knights Templar set up a prosperous network of banks and gained enormous financial influence. Their banking system allowed religious pilgrims to deposit assets in their home countries and withdraw funds in the Holy Land.

the perimeter of a triangle is 69 cm. side a is 5 cm shorter than side b. side c is twice as long as side a. find the length of each side. i need to know how to do it in 2 equations.  

equations:

a = b-5

c = 2a

a + b + c = 69

c. the king has significantly abused the colonists' rights many times over a long period of time.