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Simplify. Rationalize the denominator. \newline82+5\frac{8}{-2 + \sqrt{5}}

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Q. Simplify. Rationalize the denominator. \newline82+5\frac{8}{-2 + \sqrt{5}}
  1. Select Conjugate: Select the conjugate of 2+5-2 + \sqrt{5}.\newlineConjugate of aba - \sqrt{b}: a+ba + \sqrt{b}\newlineConjugate of 2+5-2 + \sqrt{5}: 25-2 - \sqrt{5}
  2. Multiply by Conjugate: Multiply the numerator and the denominator by the conjugate of the denominator.\newlineTo rationalize the denominator, we multiply the expression by (25)/(25)(-2 - \sqrt{5})/(-2 - \sqrt{5}).\newline82+5×2525\frac{8}{-2 + \sqrt{5}} \times \frac{-2 - \sqrt{5}}{-2 - \sqrt{5}}
  3. Simplify Numerator: Simplify the numerator by distributing the multiplication.\newline8×(25)8 \times (-2 - \sqrt{5})\newline= 8×(2)+8×(5)8 \times (-2) + 8 \times (-\sqrt{5})\newline= 1685-16 - 8\sqrt{5}
  4. Simplify Denominator: Simplify the denominator using the difference of squares formula.\newline(2+5)(25)(-2 + \sqrt{5}) * (-2 - \sqrt{5})\newline= (2)2(5)2(-2)^2 - (\sqrt{5})^2\newline= 454 - 5\newline= 1-1
  5. Combine Numerator and Denominator: Combine the simplified numerator and denominator.\newline(1685)/(1)(-16 - 8\sqrt{5}) / (-1)\newlineWhen we divide by 1-1, we change the sign of the numerator.\newline=16+85= 16 + 8\sqrt{5}

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