Since the divisor is in the form (x + #) or (x - #), This can be done by synthetic division.
First put the polynomial ion descending order: x^2 - 7x + 15
Take the coefficients of the terms and follow these steps:
3 | 1 -7 15
3 -12
___________ Bring down the 1, multiply the 3 by the 1 and place under the
1 -4 3 -7, then add.
Multiply 3 by -4, place under the 15, then add.
The bottom row is our answer. Since the problem started with a second power, the answer will start with a first power.
The bottom row are the coefficients of the terms and the last number is the remainder.
x - 4 remainder 3 ALSO WRITTEN x - 4 + 3/(x -3)