Step-by-step explanation:
log(x+2)-log(x-1)=log2
log(x+2)/(x-1)=log2
=> (x+2)=2(x-1)
=>x+2 =2x-2
=> x=4
Answer:
A
Step-by-step explanation:
The first answer is correct because we have a decay factor.
The sample is losing mass, so the number that is being multiplied by a power of x must be less than 1.
If the second answer were used, then the sample would be gaining mass.
The 3.1 °F/min rate of change of the temperature and 15 minutes change duration gives the change in temperature as 46.5 °F
<h3>How can the change in temperature be found from the rate of change?</h3>
The rate at which the temperature changed = 3.1 °F/min
The duration of the change in temperature = 15 minutes
The relationship between the change in temperature, the rate of change in temperature and the time can be presented as follows;

Where;
∆T = The required change in temperature
∆t = The duration of the change = 15 minutes
Which gives;
∆T = 3.1°F/min × 15 minutes = 46.5 °F
- The change in temperature, ∆T = 46.5 °F
Learn more about the rate of change of a variable here:
brainly.com/question/10208814
#SPJ1
<span>A water tank is 1/8 full. The tank is 3/4 full when 42 gallons are added to the tank. How much water was originally in the tank? (I rewrote it, your wording was messed up)
3/4 = 6/8
1/8 + 6/8 = 7/8 = 42 gallons
42 divided by 8 = 5 1/4
So, the answer is 5 1/4. The tank originally 5.25 gallons of water.</span>
Total cost of item = $138
Explanation:
The tax percentage = 15%
cost of item = $120
sales tax = cost of item × The tax percentage
sales tax = 120 × 15%
=120 × 0.15
sales tax = $18
Total cost of item = initial cost of item + sales tax
Total cost of item = 120 + 18
Total cost of item = $138