Answers:
x = -8/5 or x = 8/5
Sum of the first ten terms where all terms are positive = 4092
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Explanation:
r = common ratio
- first term = 4
- second term = (first term)*(common ratio) = 4r
- third term = (second term)*(common ratio) = (4r)*r = 4r^2
The first three terms are: 4, 4r, 4r^2
We're given that the sequence is: 4, 5x, 16
Therefore, we have these two equations
Solve the second equation for r and you should find that r = -2 or r = 2 are the only possible solutions. If r = -2, then 5x = 4r solves to x = -8/5. If r = 2, then 5x = 4r solves to x = 8/5.
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To find the sum of the first n terms, we use this geometric series formula
Sn = a*(1 - r^n)/(1 - r)
We have
- a = 4 = first term
- r = 2, since we want all the terms to be positive
- n = 10 = number of terms to sum up
So,
Sn = a*(1 - r^n)/(1 - r)
S10 = 4*(1 - 2^10)/(1 - 2)
S10 = 4*(1 - 1024)/(-1)
S10 = 4*(-1023)/(-1)
S10 = 4092
-9/5 or -1.8
2 - - 3 = 5
-5 - 4 = -9
Answer:
y = 5x-11
Step-by-step explanation:
The slope intercept form of a line is y =mx+b where m is the slope
y = -1/5 x-3
The slope is -1/5
Lines that are perpendicular have negative reciprocal slopes
-1 /(-1/5)
-1 * -5/1
5
The slope of the line that is perpendicular is 5
y=5x+b
Using the point (4,9)
9 = 5(4)+b
9 = 20+b
9-20 =b
-11
y = 5x-11
Answer:
1/3
Step-by-step explanation:
Answer:
She drove 200km at 100km/hr and she drove 240km at 80km/hr
Step-by-step explanation:
2×100km/hr=200km and 80km/hr×3=240km/hr
200km+240km=440km
(2+3=5)
