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A.5x=3x

B.5=3

how can we get equation B from equation A?

1 Answer

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Answer:

divide by x

Explanation:

To answer your question, you can get from A to B by dividing by x:


5x=3x\\\\(5x)/(x)=(3x)/(x)\qquad\text{only if $x\\e0$}\\\\5=3

However, this is only a valid operation if x ≠ 0. In this equation, x = 0, so that division is not valid.

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A better approach to the solution is to put the equation in standard form:

f(x) = 0

You can get there by subtracting 3x from both sides.

5x -3x = 3x -3x

2x = 0

Now, you can legitimately divide by 2 to find ...

x = 0 . . . . . . . . the reason why dividing by x is not allowed