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Which of the following is an extraneous solution of square root -3x-2=x+2?

a) x = –6
b) x = –1
c) x = 1
d) x = 6

2 Answers

1 vote

Answer:

A. x=-6

Explanation:

i got it right on edge

User Naphat Amundsen
by
7.3k points
4 votes
Hello,

Answer A (x=-6 is an extraneous solution)

√(-3x-2)=x+2
==>-3x-2>=0
==>x<= -2/3

So -3x-2=(x+2)²
==>-3x-2=x²+4x+4
==>x²+7x+6=0
==> (x=-6) or (x=-1)

if x=-6 then
√(-3*(-6)-2)=√16=4
-6+2=-4
False 4≠-4

if x=-1
√(-3*(-1)-2)=√1=1
-1+2=1
ok..


User Emeric Verschuur
by
7.0k points