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3 years ago

if the third term of an arithmetic sequence is 13 and the seventeenth term is -29 what is the eighth term

Mathematics

1 answer:

zalisa [80]3 years ago

3 0

We know that
the nth term of an arithmetic sequence can be written in the following way:

an = a1+(n - 1)d

Where a1 is the first term, and d<span> is the common difference.
</span>
for a3=13 n=3
a3=a1+(n-1)*d----> 13=a1+(3-1)*d----> 13=a1+2*d-----> equation 1

for a17=-29 n=17
a17=a1+(n-1)*d----> -29=a1+(17-1)*d----> -29=a1+16*d-----> equation 2

using a graph tool------> to resolve the equations system
see the attached figure
the solution is
a1=19
d=-3

find a8
a1=19 d=-3 n=8
a8=19+(8-1)*(-3)----> a8=19+(-21)------> a8=-2

the answer is
a8 is -2

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Answer:

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Step-by-step explanation:

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3 years ago

1. Find the measure of the side indicated (x). Round to the nearest tenth. Show your work to support your

lidiya [134]

Answer:

Is this for a Trig class? just wondering

Step-by-step explanation:

Use SOH CAH TOA to recall how the trig functions fit on a triangle

SOH: Sin(Ф)= Opp / Hyp

CAH: Cos(Ф)= Adj / Hyp

TOA: Tan(Ф) = Opp / Adj

we want to find the Hypotenuse (Hyp) and are given an angle and the adjacent side (adj) sooo use CAH , b/c it has all of the pieces

Cos(37) = Adj / Hyp

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swap Cos(37) and Hyp... an algebra trick you should know from college algebra or where ever you learned algebra

Hyp = 11 / Cos(37)

now solve with your handy TI 83 / 84 / 89 calculator :) if you don't have one go get one . :D get the 89 if you are going into engineering classes... the 83 /84 if not. (obviously there are many many other good choices, i'm not really a calculator salesman on the side :D )

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3 years ago

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KIM [24]

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3 years ago

A particle p is moving along the x-axis the displacement x metres from O can be writen as x=t^5-12t²+9 find the velocity

Lisa [10]

Answer:

$v = t (5t^{3} - 24)$

Step-by-step explanation:

We are given an expression to solve for the displacement (x), so in order to find velocity (v), we need to differentiate the function.

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Solving :

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2 years ago

29. (09.04 MC)

lara [203]

Answer:

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Step-by-step explanation:

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2 years ago