Q. Simplify. Rationalize the denominator. −9−310
Identify conjugate of denominator: Identify the conjugate of the denominator.The conjugate of a−b is a+b. Therefore, the conjugate of −9−3 is −9+3.
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 consists of the conjugate of the denominator over itself.−9−310 * −9+3−9+3
Apply distributive property: Apply the distributive property (foil method) to the numerator.Multiply 10 by each term in the conjugate (−9+3).10×(−9)+10×3=−90+103
Simplify numerator: Apply the distributive property (foil method) to the denominator.Multiply each term in (−9−3) by each term in (−9+3).(−9×−9)+(−9×3)−(3×−9)−(3×3)
Apply distributive property: Simplify the denominator.Calculate each multiplication in the denominator.81−93+93−3The middle terms cancel each other out, so we are left with:81−3=78
Simplify denominator: Write the simplified expression.The numerator is −90+103, and the denominator is 78.78−90+103
Write simplified expression: Simplify the fraction by dividing each term in the numerator by the denominator.Divide −90 by 78 and 103 by 78.−90/78=−45/39 (simplifying by dividing both numerator and denominator by 2)103/78=53/39 (simplifying by dividing both numerator and denominator by 2)
Simplify fraction: Combine the simplified terms.The final simplified expression is:−3945+3953
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