To convert from degrees Fahrenheit (°F) to degrees Celsius (°C), the correct equation is:
\[ °C = \frac{(°F - 32)}{1.8} \]
This is derived from rearranging the original formula you provided. Now, we can use this equation to find what 77°F is in °C:
\[ °C = \frac{(77 - 32)}{1.8} \] \[ °C = \frac{45}{1.8} \] \[ °C = 25 \]
So, 77°F is equal to 25°C.
The correct response from the available options would be:
°F - 32 = °C * 1.8; 25°C