Enter a recursive rule for the geometric sequence. 10, −80, 640, −5120,  a(1)= a(n)=

The value is:

a(1)=10   and   a(n)=(-8)×a(n-1)

Step-by-step explanation:

We are given a sequence as:

10, -80 , 640 , -5120 ,

since by looking at the sequence we could see that it is a geometric progression (G.P.) with common ratio -8.

Also a(1) denotes the first term of the sequence and a(n) denotes the nth term of the sequence.

a(1)=10

Also a(n)=(-8)×a(n-1)

since a(1)=10

a(2)=(-8)×10=-80

a(3)=(-8)×(-80)=640

a(4)=(-8)×640=-5120

and so on.

Hence the answer is:

a(1)=10   and   a(n)=(-8)×a(n-1)

step-by-step explanation:

given that there are two triangles j'k'l' and jkl>

the former is got by dilating the second one.

when drawn on a grid, (graph paper) coordinates of vertices of first triangle is

(6,12)j, (9,6)k and (12,9)l

side jk has length = distance between j and k

=

side j'k'=distance between j' and k'

=

ie j'k'l' has sides 1/3 of that of corresponding sides of jkl.

hence scale factor of 1/3 is used to get j'k'l'from jkl