How do you solve #1-sqrt( 7-x)= x#?

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Answer 1 · 2016-04-16T10:53:20

#x= -2" or "x=+3#

It is matter of reversing the actions given and doing so in the correct order.

Write as:# " "1-x=sqrt(7-x)#

Square both sides

#(1-x)^2=7-x#

#x^2-2x+1=7-x#

#x^2-x-6=0#

#(x+2)(x-3)=0#

#x= -2" or "x=+3#