Algebra Demystified 2nd Ed

Chapter 4 NegaTive NuMberS 87

DeMYSTiFieD / algebra DeMYSTiFieD / HuttenMuller / 000-0 / Chapter 4

PRACTICE

Use the rules for negating numbers in a product to rewrite the product.

1. 18(−3x) =


2. −4(2x)(−9y) =


3. 28(−3x) =


4. −5x(−7y) =


5. −1(−6)(−7x) =


6. 1.1x(2.5y) =


7. −8.3(4.62x) =


8. −2.6(−13.14)(−6x) =


9. 0.36(−8.1x)(−1.6y) =


10. 4(−7)(2.1x)y =

SOLUTIONS

1. 18(−3x) = −54x


2. −4(2x)(−9y) = 72xy


3. 28(−3x) = −84x


4. −5x(−7y) = 35 xy


5. −1(−6)(−7x) = −42x


6. 1.1x(2.5y) = 2.75xy


7. −8.3(4.62x) = −38.346x


8. −2.6(−13.14)(−6x) = −204.984x


9. 0.36(−8.1x)(−1.6y) = 4.6656xy


10. 4(−7)(2.1x)y = −58.8xy

Fractions and Negative Signs

Because a negative number divided by a positive number is negative, and a

positive number divided by a negative number is a negative number, a negative

sign in a fraction can go wherever we want to put it.

negative

positive

positive

negative

positive

posi

==−

ttive

PRACTICE

Use the rules for negating numbers in a product to rewrite the product.

SOLUTIONS

1. 18(−3