Answers

The simplest form of -9/21 is -3/7.

Steps to simplifying fractions

1. Find the GCD (or HCF) of the absolute values of both numerator and denominator
   GCD of 9 and 21 is 3
2. Divide both the numerator and denominator by the GCD
   -9 ÷ 3/21 ÷ 3
3. Reduced fraction: -3/7
   Therefore, -9/21 simplified to lowest terms is -3/7.

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