What is the standard normal distribution for the area to the left of z-1.72 and show work?

Area to the left of z = -1.72 = area to the right of z = 1.72

That is ALL the "working" that you will be able to show - unless you are into some serious high level mathematics. Most school teachers and many university lecturers will not be able to integrate the standard normal distribution: they will look it up in tables. (I have an MSc in Mathematical Statistics and I could do it but not without difficulty).

Pr(z < -1.72) = 0.042716