Let \( x \) be the temperature on the first day of summer in 2022. According to the information given, the temperature on the first day of summer in 2023 was 86°F, which is 6°F less than the temperature in 2022.
We can set up the equation:
\[ x - 6 = 86 \]
To find \( x \), we can add 6 to both sides of the equation:
\[ x = 86 + 6 \] \[ x = 92 \]
So, the temperature on the first day of summer in 2022 was 92°F.