Could someone please explain the best way to reduce these expressions?

4x^2

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2x^9

When you divide powers you subtract the exponents. Of course, 4/2=2.

2-9=-7. So you have:

-2x-8

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x^2+2x-8

Always check to see if anything factors.

Now, cancel what will cancel.

And how to solve this

x^2 = 14x

There isn't much to this.

Divide through by x:

x=14 or 0.