Exercise 9 Page 439

When adding or subtracting fractions, they should have the same denominator. In this exercise, we have two fractions with different denominators. 5/9 + (- 1/4) First, we can list the multiples of 9 and 4. Multiples of $9$:&9,18,27, 36, ... Multiples of $4$:&4, 8, 12, 16, 20, &24, 28, 32, 36, ... Since 36 is the least common multiple of our denominators, we can first multiply both the numerator and denominator of 59 by 4 to create a common denominator.

Next, we can multiply both the numerator and denominator of - 14 by 9 to create a common denominator.

Now that we have a common denominator, we can proceed to simplifying the expression.

When multiplying real numbers, the product will be positive if the signs are the same and it will be negative if the signs are different. cc Same Sign & Different Signs (+)(+)=(+) & (+)(-)=(-) (-)(-)=(+) & (-)(+)=(-) In our case one number is negative and one number is positive, so the product will be negative.

Before we evaluate the expression, let's first rewrite the expression so that all of the numbers are fractions.

When multiplying fractions, the product will be positive if the signs are the same and it will be negative if the signs are different.

cc Same Sign & Different Signs (+)(+)=(+) & (+)(-)=(-) (-)(-)=(+) & (-)(+)=(-) In our case one number is negative and one number is positive, so the product will be negative.

- 5/3* 4/5

MultFrac

Multiply fractions

- 5* 4/3* 5

Multiply

Multiply

- 20/15

ReduceFrac

a/b=.a /5./.b /5.

- 4/3

The quotient is - 43. We can also write this fraction as a mixed number.

- 4/3

WriteSum

Write as a sum

- (3+1/4)

WriteSumFrac

Write as a sum of fractions

- (3/3+1/3)

CalcQuot

Calculate quotient

- (1+1/3)

AddTerms

Add terms

- (1 13)

RemovePar

Remove parentheses

- 1 13