Question

The label on the cars antifreeze container clams to protect the car between -40°C and 125°C. to convert Celsius temperature in Fahrenheit temperature, the formula is C=5/9( F -32 ). Write and solve the inequality to determine the Fahrenheit temperature range at which this anti-freeze protects the car.

Answer 1

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

F = (9/5)(-40) + 32 = -40
F = (9/5)(125) + 32 = 257

Answer 2

C=(5/9)(F-32)

9C/5=F-32

F=9C/5+32 or more neatly...

F=(9C+160)/5

F(-40)=-40

F(125)=257 so

-40°<F°<257°