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How do you evaluate #(- \frac { 13} { 7} ) + ( - \frac { 3} { 5} )#?

Answer 1

Find like denominators, add numerators, simplify if possible.

To add fractions with different denominators, you must change all the fractions of interest into a fraction with like denominators. Simplify afterwards.

#(-13/7) + (-3/5)#

The lowest common denominator is #35#. Remember that whole numbers are simply a number with a denominator of #1#.

#=5(-13/7) + 7(-3/5)#
#=(-65/35) + (-21/35)#

Now with like denominators, we can add the numerators.

#=(-86/35)#

If possible, simplify; #86# does not go into #35# equally so we will leave the answer as an exact answer.

Hope this helps :)

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.