Multiplying integers is a multiplication of two whole numbers with deals about the signs.
Rules for multiplying and dividing integers
1. Product of two numbers with the same signs will be positive
Positive x positive = positive
Negative x negative = positive
2. Product of two numbers with different signs will be negative
Positive x negative = negative
Negative x positive = negative
Example
4 x 6 = 24
(-5) x (-7) = 35
(-8) x 4 = -32
(-9) x 3 = -27
The product of an integer and zero is 0
Example:
-7 * 0 = 0
0 * 9 = 0
Evaluating Variable Expressions using Integers
For Evaluating, substitute the values in the expression then simplify it
Example1:
Evaluate a2 when a = -5
Substitute a = -5 in a2
a2 = (-5)2 = -5 * -5 = 25
Example2:
Evaluate abc when a= 3, b=-2, and c = 7
Substitute a = 3, b = -2 and c = 7 in abc
abc = (3)(-2)(7) = -42
Dividing Integers
Dividing integer is same as the multiplying integers. The rule for dividing integer is
Positive ÷ positive = positive
Example: 45 ÷ 3 = 15
Negative ÷ negative = positive
Example: (-24) ÷ (-6) = 4
Positive ÷ negative = negative
Example: 18 ÷ (-9) = -2
Negative ÷ positive = negative
Example: (-32) ÷ 4 = -8
Evaluate the algebra expression using Integers
Example1:
Evaluate -34 ÷ y, if y = -17
(-34) ÷ (-17) = 2
Example2:
(uv ÷ t ) * -4 where u = -9, v = 5 and t = -3
(uv ÷ t ) * -4 = [(-9 x 5) ÷ -3] * -4
= [-45 ÷ -3] * -4
= 15 * -4
= -60