Use limit process find area of the region between graph of the function and the x axis over the indicated interval.

I have

y=-2x+3 from from 0 to 1

I have delta x= 1/n xi= 1i/n

-2(1i/n)+3 times (1/n)

I then have

(-6i)/(n^2) times n(n+1)/(2)

Did I do this correctly?