Athiidn
Answered

Join the IDNLearn.com community and get your questions answered by experts. Get the information you need from our experts, who provide reliable and detailed answers to all your questions.

in an A.P,the sum of first ten terms is -150 and the sum of next 10 terms is -550.Find the A.P

Sagot :

Crisforpidn
S10 = -150;
 the sum of next 10 terms = S20 - S10 => -550 = S20  + 150 => S20 = -700;
S10 = -150 => 2a1 + 9r = -30;
 S20 = -700 => 2a1 + 19r = -70;
Then 10r = -40 => r = -4 , and, 2a1 -36 = -30 => 2a1 = 6 => a1 = 3;
Thank you for joining our conversation. Don't hesitate to return anytime to find answers to your questions. Let's continue sharing knowledge and experiences! IDNLearn.com has the answers you need. Thank you for visiting, and we look forward to helping you again soon.