Fine the equation of line having slope m and x intercept c

fine the equation of line having slope m and x intercept c

the line passes through the point (c,0)

by the slope point form

(y-y1)=m(x-x1)

(y-0)=m(x-c) => y=mx-mc

y=mx+a
where a is unknown...
now when y=0 ,,, x=c

=>a= -mc

y=mx-mc