Question 1100329
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Probably, you want to ask:


<pre>
    Explain why     2 + 3(x – 2) = 5x – 10  (*)  is not true identity.
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<pre>
It is because the left part is 

    2 + 3x - 6 = 3x - 4,


while the right side is 5x - 10.


The left side expression differs from that of the right side.
Therefore, (*) is not an identity.


We even can go further and write a hypothetical equation

3x - 4 = 5x - 10

which implies

2x = 6  and    then   x = 3.


So, the two original expressions are equal only at x = 3,  but they are not equal identically as functions.
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