I''m stumped on this. I cant seem to properly rearrange this equation to solve for n. Can anyone help? Heres the equation: z + (na + .5n(n - 1)d) = c This equation uses five variables : z, a, b, c, n Any help is much appreciated.

Looks to be a basic quadratic equation so put it into the format of
ax^2+bx+c = 0 and use the general equation for solving quadratics.


Just to start you off:

z + (na+0.5n(n-1)d) = cna + 0.5dn^2 - 0.5nd + z-c = 00.5dn^2 + (a - 0.5d)n + z-c = 0...

Thanx alot! That definitely put me in the right direction. I just applied that to the quadratic formula and it worked just fine. Thanx again.