Find LCD: To combine the fractions, we need a common denominator. The least common denominator (LCD) for 2 and 5 is 10.
Convert to LCD: Convert each fraction to an equivalent fraction with the denominator of 10. For −21, multiply the numerator and denominator by 5 to get −105. For −53, multiply the numerator and denominator by 2 to get −106.
Combine Fractions: Now that we have common denominators, we can combine the fractions by adding the numerators. So, −105−106 equals −1011.
Simplify Result: The fraction −1011 is already in its simplest form because the numerator and the denominator have no common factors other than 1.
More problems from Simplify variable expressions using properties