if the product of 5 and a number is increased by 9 and this sum multiplied by 3, the result is 11 greater than the opposite of the number

Answer 1

3(5x + 9) = 11 + (-x)

15x + 27 = 11-x

16x = 11-27 = -16

x = -16/16 = -1

x = -1

If you get a simple solution like this it's probably accurate, but if an instructor or textbook ever had a problem like this, they're insane.