Answer:
Yes, y=5x is a direct variation and the constant of variation is 5 .
The given ratios 3: 5 and 15: 25 are equal. Because when you divide the ratio 15: 25 by 5 on both numerator and denominator, the first ratio 3: 5 can be obtained. Similarly, when you multiply the first ratio 3: 5 by 5, the ratio 15: 25 can be obtained.
The factoring method which can be considered for such a cubic tetranomial expression is; factor by grouping sum of cubes.
<h3>What factoring method can be considered for the polynomial?</h3>
It follows from the task content that the order of the Polynomial is 3 and the polynomial is a tetranomial as it contains 4 terms.
On this note, since 3x³ is not a perfect cube, it follows that the best factorisation method for such a polynomial is; factor by grouping sum of cubes.
Read more on factorisation;
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