Question

Find the common difference when a25-a12= - 52

Answer 1

Answer:common difference (d)= -4

Step-by-step explanation:

=a25-a12=-52

=a+24d-(a+11d)= -52

=a+24d-a-11d=-52

=13d=-52

=(d= -4)

Answer 2

ANSWER

Let a

1

=a

∴a

25

=a

1

+24d ...eq ( 1 )

∴a

12

=a

1

+11d ...eq ( 2 )

eq ( 1 ) - eq ( 2 )

a

1

+24d−a

1

−11d=−52

13d=−52

∴d=−4..