Q. Li Juan solves the equation below by first squaring both sides of the equation.3−2w=w+6What extraneous solution does Li Juan obtain?w=
Square both sides: Square both sides of the equation to eliminate the square root.(3−2w)2=(w+6)23−2w=w2+12w+36
Rearrange and find values: Rearrange the equation to set it to zero and find the values of w.0=w2+12w+36−(3−2w)0=w2+12w+36−3+2w0=w2+14w+33
Factor the quadratic: Factor the quadratic equation. (w+11)(w+3)=0
Solve for w: Solve for w by setting each factor equal to zero.w+11=0 or w+3=0w=−11 or w=−3
Check for extraneous solutions: Check for extraneous solutions by substituting the values of w back into the original equation.Check w=−11:3−2(−11)=−11+63+22=−525=−55=−5 (This is an extraneous solution because the square root of a positive number cannot be negative.)
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