Select Conjugate: Select the conjugate of the denominator to rationalize it.The conjugate of a number of the form a+b is a−b.Therefore, the conjugate of 8+5 is 8−5.
Multiply by Conjugate: Multiply the numerator and the denominator by the conjugate of the denominator.This will eliminate the square root from the denominator.(−2)×(8−5) / (8+5)×(8−5)
Use Difference of Squares: Use the difference of squares formula to simplify the denominator.(a+b)(a−b)=a2−b2(8+5)(8−5)=82−(5)2=64−5=59
Simplify Numerator: Simplify the numerator by distributing −2 to both terms in the conjugate.(-2) \times (8 - \sqrt{5}) = (-2) \times 8 + (-2) \times (-\sqrt{5})\(\newline= -16 + 2\sqrt{5}\)
Combine Numerator and Denominator: Combine the simplified numerator and denominator.(−16+25)/59This is the simplified form of the original expression with a rationalized denominator.
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