Is x=1/3 a possible answer? It would be if in fraction form.
or -31.
First term: a(1) = 4; common ratio: r = 2
Then:
a(n) = 4(2)^(n-1)
Check: Predict the 4th term using this formula:
a(4) = 4(2)^3 = 4(8) = 32 (correct)
A graphing calculator can do a linear regression on these points very easily. The y-intercept is 107.
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If you want to do this by hand, you can use the 2-point form of the equation for a line, then evaluate for x=0.
.. y = (100 -102)/(35 -25)*(x -25) +102
.. y =-2/10*(0 -25) +102
.. y = 107
Company A
Income = 35,000 + 0.03x
Company B
Income = 25,000 + 0.05x
set them equal to see how much of sales Julia needs to make the same income at both companies.
30,000 + 0.03x = 25,000 + 0.05x
30,000 - 25,000 = 0.05x - 0.03x
5,000 = 0.02x
5,000/0.02 = x
250,000 = x
Company A has better base salary and so would pay better if less than 250,000 sales are made. Company B has bigger percent bonus and would be a better deal if more than 250,000 sales are made.
So it's the 2nd choice.