a) There are an infinite number of possibilites, and we cannot draw graphs for you. One right triangle would have corners at (0,0), (0,10) and (5,0)
b) Have one corner at (0,10), and put two other corners at (a,0) and (-a,0). a can be any real number.
If in your problem you were given two triangles with specific side lengths, then the numbers you choose would have to agree with them.