First, subtract color(red)(7) from each side of the equation to isolate the square root expression while keeping the equation balanced:
-color(red)(7) + 7 - sqrt(x - 6) = -color(red)(7) + 3
0 - sqrt(x - 6) = -4
-sqrt(x - 6) = -4
Next, multiply each side of the equation by color(red)(-1) to eliminate the negative terms while keeping the equation balanced:
color(red)(-1) xx -sqrt(x - 6) = color(red)(-1) xx -4
sqrt(x - 6) = 4
Then, square both sides of the equation to eliminate the square root function while keeping the equation balanced:
(sqrt(x - 6))^2 = 4^2
x - 6 = 16
Now, add color(red)(6) to each side of the equation to solve for x while keeping the equation balanced:
x - 6 + color(red)(6) = 16 + color(red)(6)
x - 0 = 22
x = 22
An extraneous solution would be sqrt(x - 6) = -4