Dividing
using polynomial long division leaves a remainder of x-7. So,

Polynomial Long Division for

Step 1: Set up the division
x+3

-------

-8x
-7
Step 2: Divide the leading term of the dividend by the leading term of the divisor
- Bring down the first term of the dividend
to the quotient.
x

-------

Step 3: Multiply the divisor by the quotient and subtract from the dividend
- Multiply the divisor (x+3) by the quotient (x).
- Subtract the product
from the dividend.
x

-------

-8x - 7
Step 4: Bring down the next term of the dividend and update the divisor
- Bring down the next term of the dividend (x) to the remainder.
- Update the divisor by attaching the remainder (-8x) to it.
x

-------

-7
x + 3
Step 5: Repeat steps 2-4 until the remainder is a constant term or a polynomial of lower degree than the divisor
- Since the divisor has a higher degree than the remaining polynomial (-7), the remainder is a constant term.
- Therefore, the division is complete.
Answer:

Note: The symbol "%" represents the modulo operation, which gives the remainder when dividing two polynomials.