these two bars | | mean absolute value
here's how to find x
| x - 7| = 2
first apply the absolute rule
x - 7 = 2 x - 7 = -2
in both equations add 7 on both sides
x - 7 + 7 = 2 + 7 x - 7 + 7 = -2 + 7
then simplify the expressions
x = 9 x = 5
now combine these two solutions to get your answer
x = 9 or x = 5
hopefully my explanation helps