(i) F = (9/5)c + 32
It can be observed that points (0, 32) and (−40, −40) satisfy the given equation. Therefore, these points are the solutions of this equation.
The graph of the above equation is constructed as follows.
Therefore, the temperature in Fahrenheit is 86°F.
(iii) Temperature = 95°F
F = (9/5)c + 32
95 = (9/2)c + 32
63 = (9/5)c
c = 35
Therefore, the temperature in Celsius is 35°C.
(iv) F = (9/5)c + 32
If C = 0°C, then
F = (9/5)0 + 32
Therefore, if C = 0°C, then F = 32°F
If F = 0°F, then
0 = (9/5)c + 32
(9/5)c = 32
c = -160/9 = 17.77
Therefore, if F = 0°F, then C = −17.8°C
(v) (9/5)c = -32
Here, F = c
F = (9/5)F + 32
(9/5 -1)F + 32 = 0
(4/5)F = -32
F = -40
Yes, there is a temperature, −40°, which is numerically the same in both Fahrenheit and Celsius.