Well there are 8 years that show over 90°. Using those statistics you can show that as 8/15 for a probability.
It could be anything they are both variables.
First, simplify out the brackets:
-20 - 4n = -12
Then, combine like terms by moving the -20 to the other side
-4n = -12 + 20
-4n = 8
Divide by -4 on both sides to isolate the n
n = 8/-4
n = -2
