Solve 3x(x+2)=-18: Is -1+or-the square root of 5 Correct?

Thread starter aisha
Start date Nov 30, 2004

AI Thread Summary

The equation 3x(x+2)=-18 is solved using both completing the square and the quadratic formula. The correct solutions obtained are -1 plus or minus the square root of 5. Clarification was provided that the right-hand side of the equation is indeed -18. The discussion confirms the accuracy of the solutions derived from both methods. The focus remains on verifying the correctness of the solutions for the given equation.

Nov 30, 2004

aisha

Solve 3x(x+2)=-18 by completing square and quadratic formula. I did both methods and got -1+or-the square root of 5 i
Can someone just tell me if this is correct?

Last edited: Nov 30, 2004

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Nov 30, 2004

Gokul43201

Staff Emeritus

Science Advisor

Gold Member

Is that +18 or -18 ?

You're right if it's +18 and the RHS of the equation is " = 0 ".

Last edited: Nov 30, 2004

Nov 30, 2004

aisha

Yes sorry the equation was =-18
Thanks for checking

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