√(x -4) + 5 = 2
Note the equal sign. What you do to one side, you do to the other. Do the opposite of PEMDAS.
First, subtract 5 from both sides
√(x -4) + 5 (-5) = 2 (-5)
√(x -4) = 2 - 5
√(x -4) = -3
Next, get rid of the root by squaring both sides
√(x -4)² = (-3)²
x - 4 = (-3)(-3)
x -4 = 9
Finally, isolate the x by adding 4 to both sides
x - 4 (+4) = 9 (+4)
x = 9 + 4
x = 13
13 is your answer
hope this helps