Answer:
19.44 hours, about 19 hours 26 minutes
Step-by-step explanation:
The exponential equation that describes your caffeine level can be written as ...
c(t) = 120·(1 -0.12)^t . . . . where t is in hours and c(t) is in mg
We want to find t for c(t) = 10, so ...
10 = 120(0.88^t)
10/120 = 0.88^t . . . . . . . divide by 120
log(1/12) = t·log(0.88) . . . take logarithms
t = log(1/12)/log(0.88) ≈ 19.4386
It will take about 19.44 hours, or 19 hours 26 minutes, for the caffeine level in your system to decrease to 10 mg.
Answer:
-4m-3
Step-by-step explanation:
-0.25 times 16 is the same thing as dividing 16 by -4. 16m divided by -4 is -4m
-0.25 times 12 is the same thing as dividing 12 by -4. 12 divided by -4 is -3
Answer:
8
Step-by-step explanation:
logic
Answer:
18.
∠2 = 40
∠3 = 140
∠4 =140
19.
∠1 = 134
∠2 = 46
∠3 = 134
∠4 = 46
Step-by-step explanation:
18. Using vertical angle theorem, 1 is equal to 2 and 3 is equal to 4. Therefore 2 is equal to 40 degrees. Then since 2 and 3 are supplementary adjacent angles or a linear pair, they equal 180 when combined. 180-40 equals 140. 3 and 4 are also vertical angles so 3 = 4 and they are both 140.
19. Angles 1 & 3 and 2 & 4 are vertical angles because they are directly across from each other and share the same bisectors. You can use what you know about special angle pairs to find the measure of each angle because since 1 & 3 are vertical angles and 2 & 4 are also vertical angles, 1 is equal to 3 and 2 is equal to 4. So, since the angle formed at the right is angle 2, we can confirm that angle 4 is equal to it and therefore angles 2 and 4 are 46 degrees. Then since angles 1 & 2 and 3 & 4 are linear pairs, we can say that angle 1 + angle 2 is equal to 180 and the same for angles 3 & 4. So subtract 180 - 46 and you get 134. Therefore angles 1 and 3 are equal to 134 degrees.
