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What is the value of the expression
Picture above
Thanks

What is the value of the expression Picture above Thanks-example-1
User Chante
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1 Answer

5 votes

First, we want the fractions in the numerator to have the same denominator.

Find the LCM (least common multiple) of 5 and 10:

Multiples of 5: 5, 10, 15, 20

Multiples of 10: 10, 20

10 < 20

The LCM is 10. Divide the LCM by the smaller denominator for 2/5:


10 / 5 = 2

Multiply the numerator and denominator of the fraction by this number:


(2)/(5) \cdot (2)/(2) = (4)/(10)

We can now solve for the overall numerator:


(4)/(10) + (3)/(10) = (7)/(10)

The expression should now look like this:


((7)/(10))/(-(7)/(9))

We can multiply the numerator by the fraction's denominator within the expression's denominator:


((7)/(10))/(-(7)/(9)) = ((7)/(10) \cdot 9)/(-7) = ((63)/(10))/(-7)

We can eliminate the denominator of the expression's numerator fraction by multiplying it by the expression's denominator:


((63)/(10))/(-7) = (63)/(-7 \cdot 10) = (63)/(-70)

Find the GCF (greatest common factor) between 63 and 70:

Factors of 63: 1, 3, 7, 9, 21, 63

Factors of 70: 1, 2, 5, 7, 10, 14, 35, 70

7 > 1

GCF : 7

Divide the numerator and denominator by the GCF:


(63)/(-70) / (7)/(7) = (9)/(-10)

There is a negative sign in the denominator. Move this negative sign outside of the fraction:


(9)/(-10) = \boxed{-(9)/(10)}

The answer in simplest form will be -9/10.

User Max Marroni
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