First you have to put it into point-slope form before you can write it in slope-intercept form which is y-y1=m(x-x1)
Y-1=2(x-1)
Distribute the 2 to the x and -1
Y-1=2x-2
Move it all to one side
Y=2x-1
What is 7x5x4, it is 140 so the volume is 140in^3 its a pretty simple problem

check your calculator for the [!] factorial button.
also bear in mind that most calculators also have an [ₙPᵣ] button, to get Permuations, and you can just use that.
Tell me if this is fine. I wasn't able to edit the document you gave me, so i made one on my own. If you require a full graph, comment, and ill make it again. (I put 2, select the best one)