The information we have is:

So we can find that two coordinates are ( -2,-8 ) and ( 3,7 ) so we can use the equation to find the slope so:

So the equation now will be:

So we can replace one coordinate to find b so:

So the final equation is:
Maybe I am wrong but in my opinion you need at least to values per triangle. But in this case there are alwys just 2.
Answer:
x = 2.75
Step-by-step explanation:
3^2 +4^2 =c^2
9+16=25
5^2 =25
5-2.25= 2.75