using the equation y=mx+c where m is the slope, we can see that the slope is -15. since line s is parallel to line r it will have the same slope. now we can use the point-slope form equation to determine the equation of line s. point (10.4) is taken as (x1,y1) and the equation is (y-y1)=m(x-x1) which gives y-4=-15(x-10) you can solve this equation to get the final equation
