How do you solve 7- sqrt(x-6)=3 and find any extraneous solutions?

1 Answer
Feb 28, 2017

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