multiply rational numbers. SOL: none Objective The student will be able to: Designed by Skip Tyler, Varina High School and Nicole Kessinger Deep Run High School
Multiplying Rules 1) If the numbers have the same signs then the product is positive. (-7) (-4) = 28 2) If the numbers have different signs then the product is negative. (-7) 4 = -28
Examples 1) (3x)(-8y) 2) Write both numbers as a fraction. Cross-cancel if possible. =-16 Multiplying fractions: top # Bottom # bottom# -24xy
When multiplying two negative numbers, the product is negative. 1.True 2.False Answer Now
When multiplying a negative number and a positive number, use the sign of the larger number. 1.True 2.False Answer Now
3) = =
Multiply: (-3)(4)(-2)(-3) Answer Now
an easy way to determine the sign of the answer 3 negative signs -> Odd -> answer is negative -480 When you have an odd number of negatives, the answer is negative. When you have an even number of negatives, the answer is positive. 4) (-2)(-8)(3)(-10) Do you have an even or odd number of negative signs?
Last one! 5) Positive or negative answer? Positive - even # of negative signs (4) Write all numbers as fractions and multiply. =12
What is the sign of the product of (-3)(-4)(-5)(0)(-1)(-6)(-91)? 1.Positive 2.Negative 3.Zero 4.Huh? Answer Now