Answer:
x=-2,y=-2
Step-by-step explanation:
x+y=-4
x=-4-y--(3)
substitute (3) in (1)
5(-4-y) -3y=-4
-20-5y-3y=-4
-8y=16
y=16/-8
y=-2
substitute y in (3)
x=-4-(-2)
x=-2
20 because if you think about it 2/3 is equal to 20/30.
Answer is:
6162 years
Explanation:
The given equation to use is:
<span>N=Noe^-kt
First, we will need to define the variables of the equation as follows:
No : original amount of C-14 (at t=0)
N : amount of C-14 at certain time (t)
k : a constant equals </span><span>0.0001
t : the time in years
Now, we are given that:
The skeleton contains 54% of it's original amount of C-14. This means that:
N/No = 54% = 0.54
Substitute with this given in the equation given, we will find that the only unknown is the time (t). We can now solve for t as follows:
</span><span>N=Noe^-kt
This can be rewritten as:
N/No = </span>e^-kt
Now,
N/No = e^-kt
0.54 = e^(-0.0001t)
Take ln for both sides:
ln (0.54) = -0.0001t
-0.61618 = -0.0001t
t = 6161.86 years which is approximately 6162 years
Hope this helps :)