This can be done using synthetic division.
1 -2 -14 -5
-3 -3 15 -3
___________
1 -5 1 -8
v^2 - 5v + 1 remainder -8
OR
v^2 - 5v + 1 -8/(v + 3)
The decimal representation of any number is a linear combination of powers of 10. In other words, given a number like 123.456, we can expand it as

for any
, so the above is the same as

Similarly, we can write

Now it's a question of reducing the fraction as much as possible. We have
so

(2x +3)(2x-3)= 0
x= -3/2 x = 3/2