Answer:
The equation needed is 
The cost per ream of paper = $4
Step-by-step explanation:
Here, the cost of 5 reams of paper = $ 21
The tax on her purchase = $1
So, the actual cost of 5 reams of paper = Total Cost paid - Tax amount
= $ 21 - $ 1 = $20
So, the actual cost of 5 reams of the paper is $20.
Now, to find out the cost of 1 ream of paper:
= $4
Hence, the cost of each ream of paper = $ 4.
Answer:
It will take 13.5 minutes for the liquid to reach - 10.8°C.
Step-by-step explanation:
The initial temperature of the experiment is 0°C and as the experiment goes on, the temperature of the liquid is changing at a rate of - 0.8°C per minute.
So, the equation that models the situation is
T = 0 - 0.8t
⇒ T = - 0.8t ................. (1)
Where T is the temperature of the liquid in °C and t is the time of spending after the experiment starts in minutes.
Now, given T = - 10.8°C and we have to find the corresponding time (t) in minutes.
So, from equation (1) we get,
- 10.8 = - 0.8t
⇒ t = 13.5 minutes
Therefore, it will take 13.5 minutes for the liquid to reach - 10.8°C. (Answer)
We can write a system of equations.
x + y = 77
y = x + 5
Plug in x + 5 into the first equation:
x + y = 77
x + (x + 5) = 77
So this is our answer.
Answer:
Step-by-step explanation:
I need the answer choices to be able to answer this question
