Solve the equation 3 + 5x - 2x2 = 0

  • A \(-\frac{1}{2},-3\)
  • B 2, 3
  • C -2, 3
  • D \(-\frac{1}{2},3\)
waec 2000mathematics

The correct answer is D. \(-\frac{1}{2},3\)

\(3 + 5x - 2x^2 = 0\\

3 + 6x - x - 2x^2 = 0\\

3(1 + 2x) - x(1 + 2x) = 0\\

(3-x)(1+2x)=0\\

3-x = 0 \hspace{1mm}or \hspace{1mm}1+2x = 0\\

x = 3\hspace{1mm} x = -\frac{1}{2}\\

x = 3 \hspace{1mm}or\hspace{1mm} x =-\frac{1}{2}\)

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