Question 220807
Assume the problems is:
{{{((z-2))/((z+1))}}} = {{{5/7}}}
cross multiply
7(z-2) = 5(z+1)
:
7z - 14 = 5z + 5
:
7z - 5z = 5 + 14
:
2z = 19
:
z = {{{19/2}}}
z = 9.5
;
;
Check solution in original equation: 
{{{(9.5-2)/(9.5+1)}}} = {{{5/7}}} = .7142857
{{{7.5/10.5}}} = .7142857