Solve the equation:

https://mapleta.wlu.ca/mapleta/tmp/d...hbdeachppg.gif

https://mapleta.wlu.ca/mapleta/tmp/m...ifmbnbkchn.gif

Correct Answer:-6+7^(1/2)

can someone explain how I would obtain the answer above? I know how to actually solve for x numerically, but I don't know how to get -6+7^(1/2)