Answer:
-40 °F = -40 °C
Step-by-step explanation:
(1) F = 1.8 C + 32
If the Fahrenheit and Celsius temperatures are the same, then
(2) F = C Substitute (2) into (1)
C = 1.8C + 32 Subtract 1.8 C from each side
C – 1.8 C = 32 Combine like terms
-0.8C = 32 Divide each side by -0.8
C = -32/0.8
(3) C = -40 Substitute (3) into (1)
F = 1.8(-40) + 32
F = -72 + 32
F = -40
So, -40 °F = -40 °C
The thermometer below shows that -40 °F = -40 °C.
