Identify common denominator: Identify the common denominator for the fractions−85 and −58.The common denominator for 8 and 5 is 40.
Convert to equivalent fractions: Convert each fraction to an equivalent fraction with the common denominator of 40. For −85, multiply both the numerator and the denominator by 5 to get −4025. For −58, multiply both the numerator and the denominator by 8 to get −4064.
Add fractions with common denominator: Add the two fractions with the common denominator.−4025−4064=40−25−64
Perform subtraction in numerator: Perform the subtraction in the numerator. −25−64=−89 So, the combined fraction is −89/40.
Check for further simplification: Check if the fraction can be simplified further.The fraction −4089 is already in its simplest form because 89 and 40 have no common factors other than 1.