Question 1039297
A possible way to get lost from mistakes is to perform substitution too early.
Substituting for d may be easier than for x.


Three numbers in arithmetic sequence: {{{system(x,x+d,x+2d)}}}
and their sum:  {{{x+x+d+x+2d=30}}}
{{{3x+3d=30}}}
{{{x+d=10}}}
from which you could later use  {{{highlight_green(d=10-x)}}}.


The product of 910:
{{{highlight_green(x(x+d)(x+2d)=910)}}}
NOW SUBSTITUTE FOR d.
{{{x(x+10-x)(x+2(10-x))=910}}}
and skipping the simplification steps,
{{{highlight_green(highlight_green(x^2-20x+91=0))}}}


{{{(x-13)(x-7)=0}}}
{{{system(Either,x=13,OR,x=7)}}}
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What can be the common difference, d?  Do they both work?  Maybe.
If x=13, then d=-3;
If x=7, then d=3.


Note from description, the sum must be positive and the product must be positive.
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13, 10, 7
OR
7, 10, 13
Are the numbers.
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