Question 483054
{{{p=s+t+u}}} Start with the given equation.



{{{0=s+t+u-p}}} Subtract {{{p}}} from both sides.



{{{-u=s+t-p}}} Subtract {{{u}}} from both sides.



{{{u=(s+t-p)/(-1)}}} Divide both sides by {{{-1}}} to isolate {{{u}}}.



{{{u=-s-t+p}}} Divide and simplify.



{{{u=p-s-t}}} Rearrange the terms.



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Answer:


So the solution is {{{u=p-s-t}}}