The temperature, [tex]t[/tex], in Burrtown starts at [tex]25^{\circ} F[/tex] at midnight, when [tex]h=0[/tex]. For the next few hours, the temperature drops 3 degrees every hour.

Which equation represents the temperature, [tex]t[/tex], at hour [tex]h[/tex]?

A. [tex]t=3h+25[/tex]
B. [tex]t=-25h+3[/tex]
C. [tex]t=25h-3[/tex]
D. [tex]t=-3h+25[/tex]



Answer :

To determine which equation represents the temperature [tex]\( t \)[/tex] at hour [tex]\( h \)[/tex] in Burrtown, let's consider the given information.

1. Initial Condition:
The temperature starts at [tex]\( 25^{\circ} F \)[/tex] at midnight. This implies that when [tex]\( h = 0 \)[/tex], [tex]\( t = 25 \)[/tex].

2. Rate of Change:
The temperature drops by 3 degrees every hour. This means that for every hour that passes, the temperature decreases by 3 degrees.

To form the equation, we'll start with the initial temperature and consider the effect of the hourly decrease:

- Initial Value:
At [tex]\( h = 0 \)[/tex], [tex]\( t = 25 \)[/tex].

- Hourly Decrease:
For each hour [tex]\( h \)[/tex], the temperature decreases by [tex]\( 3 \cdot h \)[/tex].

Combining these two observations, the temperature [tex]\( t \)[/tex] at any hour [tex]\( h \)[/tex] can be modeled as:

[tex]\[ t = 25 - 3h \][/tex]

Where:
- [tex]\( 25 \)[/tex] is the starting temperature at [tex]\( h = 0 \)[/tex].
- [tex]\( -3h \)[/tex] accounts for the drop in temperature by 3 degrees each hour.

Now, let's compare our derived equation to the provided options:

- A. [tex]\( t = 3h + 25 \)[/tex] (This option suggests the temperature increases by 3 degrees each hour, which is incorrect.)
- B. [tex]\( t = -25h + 3 \)[/tex] (This option does not reflect the initial temperature correctly and has an incorrect slope.)
- C. [tex]\( t = 25h - 3 \)[/tex] (This option suggests a linear increase in temperature, then a fixed drop, which does not match the scenario.)
- D. [tex]\( t = -3h + 25 \)[/tex] (This option correctly represents the temperature starting at [tex]\( 25 \)[/tex] and decreasing by 3 degrees each hour.)

Therefore, the correct equation that represents the temperature [tex]\( t \)[/tex] at hour [tex]\( h \)[/tex] is:

[tex]\[ \boxed{t = -3h + 25} \][/tex]