WILL MEDAL;
Given that the first 5 terms of a geometric sequence are 3, x, 12, y, and 48, find, x and y. Assume both x and y are positive.

Question

WILL MEDAL;
Given that the first 5 terms of a geometric sequence are 3, x, 12, y, and 48, find, x and y. Assume both x and y are positive.

triciaal · Answer

for a geometric sequence the terms have a common ratio 
 example   term 3/term 2 = term 5/ term 4

triciaal · Answer

set up  2 sets of  ratio and solve the simultaneous equation

cwrw238 · Answer

the 5 th term is 48

so a1* r^4 = 48

where a1 = 3

from this you can find the common ratio r

triciaal · Answer

* not simultaneous equation  just quadratic   and use the positive value

triciaal · Answer

I  have x = 6 and y = 7   the ratio r  = 2

anonymous · Answer

the second term would be 4?

triciaal · Answer

no your 2nd term is x

triciaal · Answer

first 5 terms of a geometric sequence are 3, x, 12, y, and 48

anonymous · Answer

im not quite sure on how to figure it out @triciaal

triciaal · Answer

48/y = y/12 = y/12 = 12/x = x/3 
do you see this ?

anonymous · Answer

alright, would it be 6?

triciaal · Answer

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