5. The label on the car's antifreeze container claims to protect the car between [tex]\(-40^{\circ} C\)[/tex] and [tex]\(125^{\circ} C\)[/tex]. To convert Celsius temperature to Fahrenheit temperature, the formula is [tex]\(C = \frac{5}{9}(F - 32)\)[/tex]. Write and solve the inequality to determine the Fahrenheit temperature range at which this antifreeze protects the car.

A. [tex]\(-40 \ \textgreater \ \frac{5}{9}(F - 32) \ \textgreater \ 125 \quad; \quad -40 \ \textgreater \ F \ \textgreater \ 257\)[/tex]

B. [tex]\(-40 \ \textless \ \frac{5}{9}(F - 32) \ \textless \ 125 \quad; \quad -40 \ \textless \ F \ \textless \ 257\)[/tex]

C. [tex]\(-40 \ \textless \ \frac{5}{9}(F - 32) \quad; \quad -40 \ \textless \ F\)[/tex]

D. [tex]\(\frac{5}{9}(F - 32) \ \textless \ 125 \quad; \quad F \ \textless \ 257\)[/tex]



Answer :

To determine the Fahrenheit temperature range at which the antifreeze protects the car, we need to solve the inequality given the formula for converting Celsius to Fahrenheit: [tex]\( C = \frac{5}{9} (F - 32) \)[/tex].

We are given the Celsius temperature range [tex]\(-40^{\circ}C\)[/tex] to [tex]\(125^{\circ}C\)[/tex]. So we need to solve the inequality:
[tex]\[ -40 < \frac{5}{9}(F - 32) < 125 \][/tex]

Let's solve this step by step.

1. Start with the inequality:
[tex]\[ -40 < \frac{5}{9}(F - 32) < 125 \][/tex]

2. To eliminate the fraction [tex]\(\frac{5}{9}\)[/tex], multiply all parts of the inequality by [tex]\(\frac{9}{5}\)[/tex]:
[tex]\[ -40 \times \frac{9}{5} < F - 32 < 125 \times \frac{9}{5} \][/tex]

3. Perform the multiplications:
[tex]\[ -72 < F - 32 < 225 \][/tex]

4. Isolate [tex]\( F \)[/tex] by adding 32 to each part of the inequality:
[tex]\[ -72 + 32 < F - 32 + 32 < 225 + 32 \][/tex]
[tex]\[ -40 < F < 257 \][/tex]

So, the Fahrenheit temperature range at which the antifreeze protects the car is:
[tex]\[ -40^{\circ}F < F < 257^{\circ}F \][/tex]

The correct inequality for the given problem is:
[tex]\[ -40 < \frac{5}{9}(F - 32) < 125 ; -40 < F < 257 \][/tex]