Question

Solve for x: the square root of x squared minus x minus 5 is equal to 5

Answer 1

Square root both sides

Answer 2

so it would be x-x-5=25?

Answer 3

\[x^2-x-5=25\]

Answer 4

ohh yeah so i factor it and x would equal -5 and 6 right

Answer 5

now test each root in the original equation... sometimes you have to toss one of them

Answer 6

i toss of the negative right @phi

Answer 7

I think both roots work. for x=-5 we have
\[ \sqrt{(-5)^2 -(-5) - 5} \\
\sqrt{25 +5 - 5} \\
\sqrt{25}\\
5
\]
which is ok

Answer 8

ohh ok thank you :)