Answer:
f(10) = 8
Step-by-step explanation:
f(x) = 4(x - 8)
Let x = 10
f(10) = 4 ( 10-8)
= 4 ( 2)
= 8
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.
x = the weight of one steel ball y = the weight of one brass ball 2x + 5y = 13 (2 + 2)x + (5 - 2)y = 12 by solving the above system of equations we find:
x = 1.5 lbs y =2 lbs one steel ball weighs 1.5 lbs.one brass ball weighs 2 lbs.
