-1/3. Use the formula x1-x2/y1-y2
Answer: 392.99
Step-by-step explanation: Starting Principal: 300
Interest Rate: 9
Years: 3
Then solve
As the exercise says, the triangles are similar. So, we can set up proportions between correspondent sides.
In order to solve for x we can set up the proportion between the horizontal and vertical sides:

Solving this proportion for x implies 
Now you can solve for m and p using the pythagorean theorem, because both triangles are right:

Then, we know that the hypothenuse of the big triangle is m+p, so we have

which implies

The prime factorization for 135 is 3,3,3, and 5.