SOLUTION: Could you please help solve this quadratic equation using completing the square method? x^2+9x+8=0

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Question 962829: Could you please help solve this quadratic equation using completing the square method?
x^2+9x+8=0

Found 3 solutions by lwsshak3, josgarithmetic, josmiceli:
Answer by lwsshak3(11628)   (Show Source): You can put this solution on YOUR website!
Could you please help solve this quadratic equation using completing the square method?
x^2+9x+8=0
complete the square: (take 1/2 the coefficient of the x-term(9/2) and square it)
(x^2+9x+81/4)-81/4+8=0
(x+9/2)^2=81/4-32/4=49/4
(x+9/2)^2=49/4
take sqrt of both sides
x+9/2=±√(49/4)
x=-9/2±7/2
x=-16/2=-8
or
x=-2/2=-1

Answer by josgarithmetic(39617)   (Show Source): You can put this solution on YOUR website!
Completing the Square to Solve General Quadratic Equation
http://www.algebra.com/my/Completing-the-Square-to-Solve-General-Quadratic-Equation.lesson?content_action=show_dev

You will use the term to Complete The Square.

Answer by josmiceli(19441)   (Show Source): You can put this solution on YOUR website!





Take the square root of both sides


and, taking the negative square root of ,


-----------------
check:




OK

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