Presentation on theme: "Warm-up Check homework Odds w/book Evens with a neighbor"— Presentation transcript:
1Warm-up Check homework Odds w/book Evens with a neighbor “We cannot hold a torch to light another’s path without brightening our own.” – Ben SweetlandCheck homeworkOdds w/bookEvens with a neighborSections 2.1 – 2.4No more than 5 minutes!Warm-up
22.5 Multiplication of Integers Properties of Multiplicationa * b = b * aThe order of 2 numbers being multiplied does not matter.1 * a = aThe product of one & a number is that number.0 * a = 0The product of zero & a number is zero.
3The product of a number and -1 is the opposite of that number. -1 * a = -aThe product of a number and -1 is the opposite of that number.a * -b = -abThe product of a and –b is the opposite of ab. Multiplying 2 numbers with different signs is ALWAYS a negative answer.-a * - b = abThe product of –a and –b is ab. Multiplying 2 numbers with the same sign is ALWAYS a positive answer.
5Sect. 7 – Division of Real # The integer rules for division are the same as for multiplication.Same signs = positive answer-20/-4 = 5Different signs = negative answer-20/4 = -5
6Division can be written as multiplication. Reciprocals – numbers when multiplied together equal 1 (excluding 1 * 1)Reciprocal of a/b is b/aReciprocal of 4 is ¼Division w/reciprocalsTo divide “a” by “b”, you can multiply by the reciprocal of “b” and get the same answer.20/4 is the same as 20 * 1/4
7Write the division as multiplication & solve 3/5 divided by 2 =3/5 * ½ =3/103x divided by 1/3 =3x * 3 =9x-x / (-6) =-x * (-1/6) = x/6