AB + BC

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(*)  Multiplying And Adding Numbers In The Form:  ab + bc:

   A.  From algebra we can factor:

ab + bc = b(a + c)

   B.  Using numbers instead of variables we get the following:

1.  Take out the number that both sides have in common.

2.  Add the remaining numbers.

3.  Multiply the number in step 1 with the result in step 2 for the answer.

Ex [1]  15 x 12 + 15 x 8 =_________.

a)      Rewrite in the form 15 x (12 + 8).

b)      15 x 20 = 300.

c)      The answer is 300.

Ex [2]  16 x 16 + 16 x 17 =_________.

a)      Rewrite in the form 16 x (16 + 17).

b)      16 x 33 = 48 x 11.  See Double and Half.

c)      48 x 11 = 528.  See Multiplying by 11.

   C.  Ex [2] uses a variety of different methods.  This is just how I would do the problem, but there are many different ways of going about solving this problem.  This is up to you.

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