for an A.P. t17=54 and t9=30 then find the first term a and common difference d​

for an A.P. t17=54 and t9=30 then find the first term a and common difference d​

1 thought on “for an A.P. t17=54 and t9=30 then find the first term a and common difference d​”

  1. Answer:

    a = 6

    d = 3

    Step-by-step explanation:

    t 17 = 54

    t 17 = a + (n-1) d

    54 = a+(17-1)d

    54 = a + 16d..(1)

    t9 = 30

    t9= a + (n-1) d

    30 = a+(9-1)d

    30=a+8d..(2)

    1 – 2

    8d = 24

    d = 24/8

    d = 3

    put d = 3 in (2)

    30 = a + 8(3)

    30 – 24 = a

    a = 6

Leave a Comment