Answer:

Step-by-step explanation:
1) Move all terms to one side.

2) Factor
using Polynomial Division.
1 - Factor the following.

2 - First, find all factors of the constant term 210.

3) Try each factor above using the Remainder Theorem.
Substitute 1 into x. Since the result is not 0, x-1 is not a factor..

Substitute -1 into x. Since the result is not 0, x+1 is not a factor..

Substitute 2 into x. Since the result is not 0, x-2 is not a factor..

Substitute -2 into x. Since the result is not 0, x+2 is not a factor..

Substitute 3 into x. Since the result is not 0, x-3 is not a factor..

Substitute -3 into x. Since the result is not 0, x+3 is not a factor..

Substitute 5 into x. Since the result is 0, x-5 is a factor..

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⇒ 
4) Polynomial Division: Divide
by
.

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|

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
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

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5) Rewrite the expression using the above.


3) Solve for 

4) Use the Quadratic Formula.
1 - In general, given
, there exists two solutions where:

2 - In this case,
and 

3 - Simplify.

5) Collect all solutions from the previous steps.
