Question

In a sequnece u5=-3.7 and u15 =-52.3, what is the 19th term

Answer 1

u19=-71.74

Step-by-step explanation:

u5=a+4d=-3.7....(1)

u15=a+14d=-52.3....(2)

-10d=48.6

d=-48.6/-10

d=-4.86

Substitute-4.86 into....(1)

u5=a+4(-4.86)=-3.7

a+(-19.44)=-4.7

a=-3.7-(-19.44)

a=15.74

19term=a+18d=?

=15.74+18(-4.86)

=15.74+(-87.48)

19th term =-71.74