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How do you evaluate #-\frac { 9} { 10} + ( - \frac { 4} { 5} )#?

Answer 1

Skylar Adams

#-9/10+(-4/5)=-17/10#

First, find a common denominator. Since, #2times5=10# then,

#4/5times1=4/5times2/2=(4times2)/(5times2)=8/10#

Then

#-9/10+(-4/5)=-9/10+(-8/10)#

Since both fractions are negative we can factor out #-1#

Then

#-9/10+(-8/10)=-1times(9+8)/10=-1times17/10=underline(-17/10)#

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Answer 2

Zoe Adams

#-1 7/10#

#-9/10+(-4/5)#

#:.=-9/10-4/5#

#:.=((1 xx -9)-(2 xx4))/10#

#:.=(-9-8)/10#

#:.=-17/10#

#:.=-1 7/10#

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Answer 3

Genesis Amaya

To evaluate ( -\frac{9}{10} + (-\frac{4}{5}) ), simply add the two fractions together:

[ -\frac{9}{10} + (-\frac{4}{5}) = -\frac{9}{10} - \frac{4}{5} ]

To add fractions, we need a common denominator, which is 10 in this case. So, rewrite ( -\frac{4}{5} ) with a denominator of 10:

[ -\frac{4}{5} = -\frac{4 \times 2}{5 \times 2} = -\frac{8}{10} ]

Now, add the fractions:

[ -\frac{9}{10} - \frac{8}{10} = -\frac{9 - 8}{10} ]

[ = -\frac{17}{10} ]

So, ( -\frac{9}{10} + (-\frac{4}{5}) = -\frac{17}{10} ).

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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.