Identify Conjugate: Identify the conjugate of the denominator.The conjugate of a−b is a+b. Therefore, the conjugate of −9−2 is −9+2.
Multiply by Conjugate: Multiply the numerator and the denominator by the conjugate of the denominator.To rationalize the denominator, we multiply the expression by a fraction equivalent to 1 that has the conjugate of the denominator in both the numerator and the denominator.−9−210 * −9+2−9+2
Apply Distributive Property: Apply the distributive property to multiply the numerators and the denominators.Numerator: 10×(−9+2)=−90+10×2Denominator: (−9−2)×(−9+2)=(−9)2−(2)2=81−2
Simplify Denominator: Simplify the denominator. 81−2=79
Write Simplified Expression: Write the simplified expression.The simplified expression with a rationalized denominator is (−90+102)/79.
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