SOLUTION: The problem is I completely do not understand It states solve using the principle of zero products (2x + 2/5)(4x - 1/7)= 0 Can anyone show me how to do this?

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Question 227120: The problem is I completely do not understand
It states solve using the principle of zero products
(2x + 2/5)(4x - 1/7)= 0
Can anyone show me how to do this?
Found 2 solutions by solver91311, tam67:
Answer by solver91311(24713) (Show Source):
You can put this solution on YOUR website!

The answer is no. No one can show you how to solve this because, the way you have stated the problem, there is nothing to solve. Unless your expression has a relationship to some other value or expression, then your expression is simply something into which you can insert any values you like. Compare this to English -- you have tried to write a sentence, but have only supplied the subject of the sentence. You haven't supplied the verb. In mathematics, the verb is either the equals sign or one of the inequality signs.

On the other hand, if what you REALLY meant was:

then we can do something.

Remember the Zero Product Rule:

if and only if or .

For the problem I assumed you to mean,

or

All you need to do is solve these two single variable linear equations to determine the two values that make your equation a true statement.

John

Answer by tam67(1) (Show Source):
You can put this solution on YOUR website!
I think I have figured this out I'll try to explain it in detail but please let me know if I'm right or wrong.
(2x + 2/5)(4x - 1/7)= 0
I take the first set of ( ) and set it equal to zero:
2x + 2/5 = 0
2x + 2/5 - 2/5 = -2/5
Then solve for x: The 2 on the left is the same as 2/1, and we can multiply each side by the reciprocal, which is 1/2
(1/2)2x = -2/5(1/2)
x = -2/10 =-1/5

Now I'll plug in -1/5 for x
(2(-1/5) + 2/5)(4(-1/5) - 1/7)= 0
(-2/5 + 2/5)(-4/5 - 1/7)
0(28/35 -5/35)
0(23/35)=0

now the same for the second ( )
4x - 1/7 = 0
4x - 1/7 + 1/7 = 1/7
(1/4)4x = 1/7(1/4)
x = 1/28

Now I plug in 1/28 for x
(2(1/28) + 2/5)(4(1/28) - 1/7)= 0
(2/28 + 2/5)(4/28 - 1/7)
(10/140 + 56/140)(20/140 - 20/140)
66/140(0) = 0
Please let me know how I done