Hope it will help the formula SOHCAHTOA means Sin=oppsite\hypotenuse Cos=adjacent\hypotenuse and Tan=opposite\adjacent
With the true and the right negative
the square root of 81 is 9
|x| this means absolute value making what ever number in the inside positive UNLESS you have a negative out front. Ex |8|=8. -|8|=-8. |-8|=8