At what temperature (degrees fahrenheit) is the fahrenheit scale reading equal to (a) 6 times that of the celsius and (b) 1/5 times that of the celsius?

The relationship between temperature in degrees Fahrenheit, F, and degrees Celsius, C, is

F = 1.8C + 32

Part a.

If F = 6C, then

6C = 1.8C + 32

6C - 1.8C = 32

4.2C = 32

C = 7.62

Therefore, F = 6*7.62 = 45.71

Answer: 45.7 °F (nearest tenth)

Part b.

When F = (1/5) C, then

0.2C = 1.8C + 32

0.2C - 1.8C = 32

-1.6C = 32

C = - 20

Therefore, F = 0.2*-20 = - 4

Answer: - 4 °F