Question 1060698
Let the triplets' age be x, the sister's age is then x-5.
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{{{x^3(x-5)=75749+x+x+x+x-5}}}
{{{x^4-5x^3=4x+75744}}}
{{{x^4-5x^3-4x-75744=0}}}
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Graphing the equation,
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*[illustration dx9.JPG].
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There is one solution that is useful.
{{{x=18}}}
So then,
{{{x-5=18-5}}}
{{{x-5=13}}}