What is the missing exponent?

(Equation will be posted in comments)

Question

What is the missing exponent?

(Equation will be posted in comments)

prominer10000 · Answer

(6^???)^-4 = 6^20

Hopefully this isn't confusing. I tried my best. 
But basically the ??? is the missing exponent.

thesmartone · Answer

$\Large (6^x)^{-4} = 6^{20}$

Where x is the exoponent we're looking for

You need to use this exponent property to solve. 

$\Large (a^b)^c = a^{bc}$

and then you use this

If
$\Large x^y = x^z$

Then
$\large y = z$

prominer10000 · Answer

Sorry, I didn't respond for like 3 mins, website was lagging for me.
Anyway, I did -4 x -5 and got 20.
Does that mean the answer is -5?

Or am I wrong?

prominer10000 · Answer

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