" Life is not a problem to be solved but a reality to be experienced! "
© Copyright 2013 - 2024 KUDO.TIPS - All rights reserved.
b = -8
Un = -99
n ?
Un = a + (n-1)b
-99 = 21 + (n-1)(-8)
-99 = 21 - 8n + 8
8n - 8 - 21 - 99 = 0
8n - 128 = 0
8n = 128
n = 128/8
n = 16
CMIIW ^_^