what does the x mean in 8x=-32?

When you see a number folllowed by a letter, without anything inbetween, there is really an invisable times sign between them.

so

8x  means  8 * x

The x is used instead of a box.

so you can think of 

 \(8*x=8*\boxed{\color{white}af}=-32\\ 8*\boxed{\color{white}df}=-32 \)

So what times by 8 = -32 ?        The answer will be what x equals

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