How do you solve $x =sqrt { -3x+40}$ and find any extraneous solutions?

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Answer 1 · 2017-01-24T17:22:19

x=5, -8

Square both sides to have $x^2= -3x+40$

Or, $x^2 +3x -40=0$

This can be factorised as (x+8)(x-5)=0

Solution is therefore x=5 , -8

There are no extraneous solution

How do you solve x =sqrt { -3x+40}x =sqrt { -3x+40} and find any extraneous solutions?