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Solve by the factorization method: 2x2 + x - 1 = 0-1/2, 1-1, -1/2-1, 1/21/2, 1

User Anilbey
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1 Answer

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Step-by-step explanation

We must solve by the factorization method the quadratic equation:


2x^2+x-1=0.

1) First, we rewrite the equation above as:


\begin{gathered} 2x^2+2x-x-1=0, \\ 2x(x+1)-(x+1)=0. \end{gathered}

2) Taking (x + 1) as a common factor, we have:


(2x-1)(x+1)=0.

From the last equation, we read the roots:


\begin{gathered} 2x-1=0\Rightarrow2x=1\Rightarrow x=1/2, \\ x+1=0\Rightarrow x=-1. \end{gathered}Answer

-1, 1/2

User Tejas Gokhale
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