Identify Conjugate: Identify the conjugate of the denominator.The conjugate of a−b is a+b. Therefore, the conjugate of −7−5 is −7+5.
Multiply by Conjugate: Multiply the numerator and the denominator by the conjugate of the denominator.To rationalize the denominator, we multiply both the numerator and the denominator by the conjugate of the denominator.(−7−5)×(−7+5)10×(−7+5)
Apply Difference of Squares: Apply the difference of squares formula to the denominator.The difference of squares formula is (a−b)(a+b)=a2−b2. Applying this to the denominator we get:(−7)2−(5)2=49−5=44
Distribute Numerator: Distribute the numerator.Now we distribute 10 across the conjugate in the numerator:10×(−7)+10×5=−70+105
Combine Results: Combine the results to write the final answer.The rationalized expression is:(−70+105)/44
Simplify Expression: Simplify the expression if possible.We can simplify the expression by dividing both terms in the numerator by the denominator:(−4470)+(44105)This simplifies to:(−2235)+(2255)
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