Answer:
$
Step-by-step explanation:
÷
= 

Hope this helps
If this exact question is repeatedly deleted, it's probably because of the ambiguity of the given equation. I see two likely interpretations, for instance:

or

If the first one is what you intended, then

and it follows that
2<em>k</em> + 8 = 3 ==> 2<em>k</em> = -5 ==> <em>k</em> = -5/2
If you meant the second one, then

which would give
<em>k</em> + 9 = 3 ==> <em>k</em> = -6
And for all I know, you might have meant some other alternative... When you can, you should include a picture of your problem.
9514 1404 393
Answer:
a) 600
b) see below
c) 1.26 hours
Step-by-step explanation:
a) The value of y when x=0 is the coefficient of the exponential term:
y = 600·3^(-0) = 600·1 = 600
There were 600 atoms to start.
__
b) see attached for a graph
__
c) The graph shows 150 atoms at t = 1.26, about 1.26 hours after the start of time counting.
If you want to find that value algebraically, substitute for y and solve for x. Logarithms are involved.
150 = 600·3^(-x)
150/600 = 3^(-x)
log(1/4) = -x·log(3)
x = -log(1/4)/log(3) = log(4)/log(3) ≈ 1.2618595
After about 1.26 hours, there were 150 atoms.
<span>The sum of 324, 435, and 546 is 1305. If this number were to be expressed by the base of 7, we would need to figure out what value of exponent would satisfy the requirement. This can be done by setting up an equation where 7 to the power of x must equal 1305. Using logarithms, one can solve for x and find it to be 3.6866853. Thus the sum of the aforementioned numbers, expressed in by the base of 7, is 7^3.6866853.</span>
You go down to the negative number x is first and then you go to the positive number which is y