Question 159464
A linear equation has the form,
{{{f(x)=mx+b}}}
Let's use the values you provide and solve for m and b.
First value,
{{{f(x)=mx+b}}}
{{{4=m(1)+b}}}
1.{{{m+b=4}}}
Second value,
{{{f(x)=mx+b}}}
{{{8=m(3)+b}}}
2.{{{3m+b=8}}}
Subtract eq. 1 from eq. 2,
{{{3m+b-(m+b)=8-4}}}
{{{2m=4}}}
{{{m=2}}}
From eq. 1,
1.{{{m+b=4}}}
{{{2+b=4}}}
{{{b=2}}}
The linear equation is,
{{{f(x)=2x+2}}}