Question

if the first terms of an arithmetic sequence is 5 what could be sum of the first terms​

Answer 1

Answer:

There is a formula for the sum of

n

terms of an A.P.

S

n

=

n

2

[

2

a

+

d

(

n

−

1

)

]

FRom the information given, we know that:

n

=

10

a

=

5

,

d

=

−

8

substitute the values

S

10

=

10

2

[

2

(

5

)

−

8

(

(

10

)

−

1

)

]

S

10

=

5

[

10

−

80

+

8

]

S

−

10

=

5

×

−

62

=

−

310

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