math..solve for X
posted by M.A. on .
The sum of the first X consecutive even numbers is 930. Find X.
10
35
30
41
Explain your solution.

so we want
2 + 4 + 6 + ... = 930
this is an arithmetic series where
a=2 , d=2 , n = ?
n/2[2a + (n1)d) = 930
n/2[4 + (n1)(2)] = 930
n^2 + n  930 = 0
(n+31)(n30) = 0
n = 30 or n=31, but n has to be a positive whole number.
there were 30 terms