The answer is x4 + 7x3 - 2x2 -9x - 3 with a remainder of -10.
Long division with polynomials is very similar to regular long division. The important factor to remember during the whole process is to compare the variable in the divisor (what you are dividing by) to the leading variable in the dividend (what is getting divided).
For the first step, x goes into x5 4 times. Another way to think of this is by dividing x5/x, which will give you x4. After writing that at the beginning of your quotient expression, multiply the quotient by the divisor to create an expression of subtraction. Each expression should have a negative sign at the beginning.
Keep repeating those steps to find your answer. This picture will hopefully make things clearer.