👤

find the sum of the first 15 terms of the arithmetic sequence 17 12 and 72​

Sagot :

Step-by-step explanation:

An= a1 +( n-1 ) d

A15= 17 + (15-1 ) d (not sure dahil sa series mo)

A15= 17 + (14) d

A15= 17 + ( )

A15= (answer)

sorry can you make it more clearer for me to help you