Question 1112042
r = 2p + ps 
r = p(2+s)    factored out p 

Divide both sides by 2+s:

r/(2+s) = p,   this is true as long as s+2 is not 0  (s is not -2)
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Ans:  {{{ highlight( p =  r/(s+2) ) }}}    {{{ s <> -2 }}}
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