Question 108747
It already is a formula, you just need to substitute a value.
{{{f(x)=-(4/3)x +5}}}
Substitute for x the number 6 wherever it occurs.
{{{f(x)=-(4/3)x +5}}}
{{{f(6)=-(4/3)(6) +5}}}
{{{f(6)=-(4/cross(3))cross(6)2 +5}}}
{{{f(6)=-8+5}}}
{{{f(6)=-3}}}