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Determine whether the conjecture is true or false. If false, give a counterexample.

Given: x2+4=8
Conjecture: x=−2

User Quack
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2 Answers

4 votes
I think it is False, x=2

User Joel Spolsky
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5 votes

We start with the given equation


x^(2) + 4 = 8

Now, we solve the equation, we subtract 4 on either side,


x^(2) +4 -4 = 8-4


x^(2) = 4


x = √(4)


√(4 ) = +2 and -2

x = +2 or -2

So, x= +2 and x =-2

Since the given conjuncture says X=-2, we can conclude that the given conjuncture is TRUE

User Bitsmack
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