13x - 6y = 22
x - y = 6
6(x-y) = 6*6
6x - 6y = 36
subtract both the equations
13x - 6x -6y + 6y = -14
7x = -14
x = -2
13*-2 -6y=22
-26 -6y=22
-6y = 48
y = -8
answer: x = -2
y = -8
well, you saw it on the previous exercise, 8.25 x 10⁻⁶, it <u>looks</u> like 8.25 is some value between 1 and 10, but is not really, the 10⁻⁶ is disguising that is really much smaller than that, in fact much smaller than even 1.
Answer:
Total, 2 milkshakes, and 3 cokes would cost $12.50
Step-by-step explanation:
The cokes cost $11.50 and the milkshakes $10.00
Answer:
The bone is 14572 years old.
Step-by-step explanation:
There is 17% as much Carbon-14 in the ancient bones as from current bones and the decay constant is given as 0.0001216 for time in years.
The equation for radioactive decay is N = N₀ e^(-λt)
where t = time in years
λ = decay constant
N = final amount of carbon
N₀ = initial amount of carbon.
There is 17% as much Carbon-14 in the ancient bones as in current bones. So,
N = 17% of N₀
N = 0.17N₀
So, N/No = 0.17.
N = N₀ e^(-λt)
N/N₀ = e^(-λt)
0.17 = e^(-0.0001216t)
ln (0.17) = -0.0001216t
-0.0001216t = -1.7719568
t = -1.7719568/-0.0001216
t = 14572 years
