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Need help with hw I'm stuck

User Tramel
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1 Answer

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The quadratic formula is:


\begin{gathered} \frac{\text{ -}b\pm\sqrt[2]{b^2\text{ -4ac}}}{2a} \\ The\text{ }equation\text{ }is: \\ 2x^2+3x\text{ -}5=4 \\ 2x^2+3x\text{ -}5\text{ -4=0} \end{gathered}

We need to equal to zero before using the formula.

Noah's mistake was that he stated c=-5 when c= -9


\begin{gathered} \frac{\text{ -}b\pm\sqrt{b^2\text{ -4ac}}}{2a} \\ =\frac{-3\pm\sqrt{(\text{ -3\rparen}^2\text{ -4\lparen2\rparen\lparen-9\rparen}}}{2(2)} \\ =\frac{-3\pm\sqrt{9\text{ +72}}}{4} \\ =(-3\pm√(81))/(4) \\ =(-3\pm9)/(4) \\ \\ x1=(-3+9)/(4) \\ =(6)/(4)=(3)/(2)=1.5 \\ \\ x2=(-3-9)/(4) \\ =(-12)/(4) \\ =\text{ -3} \end{gathered}

x = 1.5 or x = -3

User Alberto Perez
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