Geometric sequence

In the geometric sequence is a4 = 20 a9 = -160. Calculate the first member a1 and quotient q.

Result

q =  -1.516
a1 =  -5.743

Solution:

Solution in text q =
Solution in text a__1 =
Solution in text a__1 = : Nr. 1
Solution in text a__1 = : Nr. 1

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