Math CentralQuandaries & Queries


Subject: find the product of each
Name: jennifer
Who are you: Student

I am having a hard time with math please help me.
Find the product of each

Hi Jennifer,

There is an understood multiplication symbol between the 8 and the x in 8x. Likewise there is an understood multiplication symbol between (8x) and (-4). Thus you can think of (8x)(-4) as (8 times x) times (-4) or with symbols

(8 x x) x (-4)

Since multiplication is commutative (that is you can perform a string of multiplications in any order you want) you can write this as

(8) x (-4) x x = -32 x x

Again using the convention of the understood multiplication

-32 x x = -32x


(8x)(-4) = -32x

Now let me try the 4th problem, (6a)(3a)(-b2). Making the understood multiplication explicit this is


and using the commutative property of multiplication

(6xa)x(3xa)x(-b2) = 6 x 3 x a x a x (-b2) = 18 x a2 x b2 = 18a2b2


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