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# Multiplying both sides of an equation by x^2 watch

1. , apparently.

Why is this the case? Does not equal ?

Edit: This is in the context of an inequality, not an equation. I do not know if this applies to equations, it merely appeared as an example in my textbook and I would like to understand why.
2. 6/x times x just equals 6. The x cancels.
3. (Original post by Illidan2)
, apparently.

Why is this the case? Does not equal ?

is a common factor in both the numerator and denominator, so cancels out (provided that )
4. Correct me if wrong, but surely 6/x × x= 6? If you had 2/5 × 5 it would be 2, so doesn't it work the same way with variables? So therefore 6/x × x^2 = 6x.
5. Oh! I see. Now that it has been pointed out, it seems so obvious to me. Thank you, guys!
6. (Original post by Illidan2)
, apparently.

Why is this the case? Does not equal ?

Edit: This is in the context of an inequality, not an equation. I do not know if this applies to equations, it merely appeared as an example in my textbook and I would like to understand why.
Multiplying by just x cancels out the x dividing the 6 and leaves just 6.

Think of it without at x but just as a number eg 7
(6/7) x 7 = 6 not 6*7
7. (Original post by Illidan2)
, apparently.

Why is this the case? Does not equal ?

Edit: This is in the context of an inequality, not an equation. I do not know if this applies to equations, it merely appeared as an example in my textbook and I would like to understand why.
it does but in terms of inequalities when multiplying you should always multiply by the square as x can be negative or positive. If x was negative it would flip the sign but we don't know if its negative or positive so we square it. x^2 will always be positive

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