PLS HELP ME The sum of the first 20 terms of an arithmetic sequence with a common difference of 3 is 650. Find the first term.

Sagot :

Answer:

Solution:

n = 650, d = 3, [tex]a_{1}[/tex] = ?

[tex]a_{n} = a_{1} + ( n - 1) d\\[/tex]

[tex]650 = a_{1} + ( 649) 3[/tex]

650 = [tex]a_{1}[/tex] + 1947

[tex]a_{1} + 1947 = 650[/tex]

           [tex]a_{1}\\[/tex]  = 650 - 1947

            [tex]a_{1}[/tex]  = - 1297

Please subscribe my youtube channel: https://bit.ly/2Y2XAZa

Step-by-step explanation: