Sunshine2: how does x=8?
from the equation 5^(4-x)=1/625
Hi Sunshine,
You must be a clever year 7 to be getting questions like this already.
(x
-a) /1 = 1/ (x
+a)
or alternatively
1/ (x
-a) = (x
+a) /1
If you write these as upright fractions you will see more clearly what I am trying to say.
Basically if something is raised to a negative power, you can get rid of the negative power by swapping the thing it belongs to, to the other side of the fraction line.
so
4
-2=1/(4
2)
5
-3/4 = 1 / (4*5
+3)
(6 * 2
-4) / (-7 * 3
-1) = (6 * 3
+1) / (-7* 2
+4) => (6*3) / (-7*16) => 18/ (-112) => -9 / 56 Note: the -7 is not and exponent so you leave it alone.
This gets a little more complicated than your question but see if you can work out what i am trying to tell you.
I would like you to let me know if you understand or if you want it explained me simply.
+118653 
