Answer: a - 4.512 hours
b - 1.94 hours
Step-by-step explanation:
Given,
a) A(t) = 10 (0.7)^t
To determine when 2mg is left in the body
We would have,
A(t) = 2, therefore
2 = 10(0.7)^t
0.7^t =2÷10
0.7^t = 0.2
Take the log of both sides,
Log (0.7)^t = log 0.2
t log 0.7 = log 0.2
t = log 0.2/ 0.7
t = 4.512 hours
Thus it will take 4.512 hours for 2mg to be left in the body.
b) Half life
Let A(t) = 1/2 A(0)
Thus,
1/2 A(0) = A(0)0.7^t
Divide both sides by A(0)
1/2 = 0.7^t
0.7^t = 0.5
Take log of both sides
Log 0.7^t = log 0.5
t log 0.7 = log 0.5
t = log 0.5/log 0.7
t = 1.94 hours
Therefore, the half life of the drug is 1.94 hours
Answer:3x² - 9x - 12 =
3(x² - 3x - 4) =
3(x² + x - 4x - 4) =
3(x(x+1)-4(x+1)) =
3(x+1)(x-4)
Step-by-step explanation:
Answer:
23
Step-by-step explanation:
supplementary angles: 180-85 = 95
95 = 5x-20 ( i forgot the name of the rule, something relating to same side interior angles i think)
115 = 5x
23= x
hope that helped
Answer:

Step-by-step explanation:

Subtract x from both sides.


Square both sides.


Subtract x²-6x+9 from both sides.


Factor left side of the equation.

Set factors equal to 0.


Check if the solutions are extraneous or not.
Plug x as 2.

x = 2 works in the equation.
Plug x as 6.

x = 6 does not work in the equation.