Question

for ap t4=20and t7=32. find a,d and tn.​

Answer 1

Step-by-step explanation:

t4 = 20

a+3d = 20..........(1)

t7= 32

a+6d=32.......... (2)

solve both as linear equation.........

subtract (2) by(1)

a+6d=32

a+3d = 20

___________

0+3d= 12

d= 4

substitute d=4 in (1)

a+3d = 20

a=8

now u can easily find tn by putting formula for tn

i. e

tn= a+(n-1) d

Answer 2

Answer:

a = 8

d = 4

tn = 4n + 4

Step-by-step explanation:

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