SOLUTION: {{{sqrt(5-x)=5-x^2}}}

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Question 687807: sqrt%285-x%29=5-x%5E2
Answer by KMST(5347) About Me  (Show Source):
You can put this solution on YOUR website!
If your problem was sqrt%285-x%29=5-x%5E2,
the first step to solve it would be squaring both sides of the equal sign.
That may introduce some extraneous solutions, but we can check the solutions and eliminate the ones that do not work.
sqrt%285-x%29=5-x%5E2 --> 5-x=%285-x%5E2%29%5E2 <--> 5-x=25-10x%5E2%2Bx%5E4 <--> highlight%28x%5E4-10x%5E2%2Bx-20=0%29
My problem at this point is that I cannot find exact solutions.
By graphing, or by smart guess and check, I can find as approximate solutions
-2.7913, -1.562, 1.791, and 2.562.
However, -2.7913, and 2.562 make 5-x%5E2 negative,
so they are not solutions of the original sqrt%285-x%29=5-x%5E2 equation.
We are left with -1.562, and 1.791 as approximate solutions