Evaluate a-2 for a = 8. I have no clue what it is..

Question

debbieg · Answer

A variable is just a "placeholder" for a number here. So you just "plug in" the value for a into the expression, and then simplify it.

I'll do a different one as an example:

Evaluate z+5 for z=3

So I put in a "3" in place of the "z":

3+5=8

Got it? You try it for your problem now. :)

anonymous · Answer

My options were 1/-64 1/-16 1/16 and  –64 and I got none of them, I still don't get it.

amistre64 · Answer

then youve most likely omited the exponent ^ part

anonymous · Answer

Oh, is it -64?

amistre64 · Answer

no, but it does have a 64 in it

amistre64 · Answer

$$8^{-2}=\frac{1}{8^2}$$

anonymous · Answer

it's 1/-64? right?

amistre64 · Answer

there would be no negative in it ... which makes me wonder about these options

amistre64 · Answer

i would assume thats the "most correct" option tho .. assuming that youve left out some of it in the post

anonymous · Answer

oh sorry it's 1/64.. That was another option.

amistre64 · Answer

:)  well, id go with the 1/64 then

debbieg · Answer

lol... yeah, knowing that the -2 was a power would have been useful. :) If you don't like the equation editor, just use a ^ and ( ) as necessary:

a^(-2)  is unambiguous, and means something much different from a-2   :)