Identify Conjugate of Denominator: 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 fraction by a form of 1 that will eliminate the square root in the denominator. This form of 1 is the conjugate of the denominator over itself.(−9−29)×(−9+2−9+2)
Multiply Numerator: Perform the multiplication in the numerator.Multiply 9 by the conjugate of the denominator.9×(−9+2)=−81+92
Multiply Denominator: Perform the multiplication in the denominator.Multiply the denominator by its conjugate. This is a difference of squares.(−9−2)∗(−9+2)=(−9)2−(2)2=81−2
Simplify Denominator: Simplify the denominator.Calculate the difference in the denominator.81−2=79
Write Simplified Expression: Write the simplified expression.Combine the simplified numerator and denominator.(−81+92)/79
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