Question

The label on the car's antifreeze container claims to protect the car between −30°C and 130°C. To convert Celsius temperature to Fahrenheit temperature, the formula is C = 5 over 9 (F − 32). Write and solve the inequality to determine the Fahrenheit temperature range at which this antifreeze protects the car.

A. −30 > 5 over 9 (F − 32) > 130; −22 > F > 266
B. −30 < 5 over 9 (F − 32) < 130; −22 < F < 266
C.−30 < 5 over 9 (F − 32); −22 < F
D. 5 over 9 (F − 32) < 130; F < 266

Answer 1

B

Explanation:

I took the test

Answer 2

we know that

`C = (5)/(9)(F-32)\\ \\F=(9)/(5)C+32`

Step
`1`

Find the inequality

we know that

`C = (5)/(9)(F-32)` --------> equation
`1`

and

`-30\° < C < 130\°`

substitute the equation
`1` in the inequality

`-30\° < (5)/(9)(F-32) < 130\°`

Step
`2`

Convert
`-30\°C` to F

substitute in the formula

`F=(9)/(5)*(-30)+32\\ \\F= -22\°`

Step
`3`

Convert
`130\°C` to F

substitute in the formula

`F=(9)/(5)*(130)+32\\ \\F= 266\°`

therefore

`-22\° < F < 266\°`

the answer is the option

B. −30 < 5 over 9 (F − 32) < 130; −22 < F < 266