Question 923975
p, Peter and m, Mary.
x, how many years to pass;
{{{(p+x)(m+x)=96}}}


{{{x^2+px+mx+pm=96}}}
{{{x^2+(p+m)x+pm-96=0}}}
Assuming using the given values would make the solution easier,
{{{x^2+10x+21-96=0}}}
{{{x^2+10x-75=0}}}
That is factorable.
{{{(x-5)(x+15)=0}}}
Only the positive solution makes sense.
{{{highlight(x=5)}}}