solving an equation with a radical

Question

what are the solutions to the equation: the square root of x+5 + the square root of x-5 = 10

Answer 1

√(x+5) + √(x-5) = 10

 

√(x+5) = 10 - √(x-5)

 

Square both sides:  x+5 = 100 - 20√(x-5) + x-5

 

Isolate the remaining radical:   20√(x-5) = 90

 

                                              √(x-5) = 4.5

 

                                                 x-5 = 20.25

 

                                                    x = 25.25