How do you solve sqrt[x+2]=sqrt[4-x] and find any extraneous solutions?

1 Answer
Oct 10, 2017

x=1

Explanation:

"to access the contents of the radicals"

color(blue)"square both sides"

•color(white)(x)sqrtaxxsqrta=(sqrta)^2=a

(sqrt(x+2))^2=(sqrt(4-x))^2

rArrx+2=4-x

"add x to both sides"

x+x+2=4cancel(-x)cancel(+x)

rArr2x+2=4

"subtract 2 from both sides"

2xcancel(+2)cancel(-2)=4-2

rArr2x=2

"divide both sides by 2"

(cancel(2) x)/cancel(2)=2/2

rArrx=1

color(blue)"As a check"

Substitute this value into the equation and if both sides are equal then it is the solution.

"left side "=sqrt(1+2)=sqrt3

"right side "=sqrt(4-1)=sqrt3

rArrx=1" is the solution"

There are no other solutions hence no extraneous solutions.