E^2=0.36 take the square root of both sides
e=±0.6
Answer:
18 minutes
Step-by-step explanation:
A = A₀ (½)^(t / T)
where A is the final amount,
A₀ is the initial amount,
t is the time,
and T is the half life.
A = 140 when t = 10. Solve for the half life:
140 = 700 (½)^(10 / T)
0.2 = ½^(10 / T)
log 0.2 = (10 / T) log 0.5
10 / T = 2.32
T = 4.31
When A = 40, t is:
40 = 700 (½)^(t / 4.31)
0.057 = ½^(t / 4.31)
log 0.057 = (t / 4.31) log 0.5
t / 4.31 = 4.13
t = 17.8
Rounded to the nearest whole number, it takes 18 minutes.
4¹/₃x = ⁵/₁₂x - 6
3¹¹/₁₂x = -6
x = -1²⁵/₄₇
Answer:
695
Step-by-step explanation:
Z-12=6
you take the 12 and add it to both sides making it look like:
z-12+12=6+12
which also looks like
z-0=6+12
z-0 = z
so now you have
z=6+12
6+12 = 18
SO Z=18!!!
your answer is 18
