Question

If the common difference of an

arithmetic sequence is 4 and T(6)=15,

find the first term of the sequence.
​

Answer 1

Step-by-step explanation:

d = 4

T(6)=15

a + 5d = 15

a + 20 = 15

a = -5

so, the first term of the sequence is - 5

Answer 2

Answer:

Step-by-step explanation:

d=4

a6=15

a6=a1+(n-1)d

15=a1+(6-1)4

15=a1+5x4

15=a1+20

15-20=a1

-5=a1

Step-by-step explanation:

Hope it helps you!!