Answer: choice B) a35 = -118
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Explanation:
When n = 5, an = 32 as shown in the first column of the table. This means the fifth term is 32. Plug in those values to get
an = a1+d(n-1)
32 = a1+d(5-1)
32 = a1+4d
Solve for a1 by subtracting 4d from both sides
a1 = 32-4d
We'll plug this in later
Turn to the second column of the table. We have n = 10 and an = 7. Plug those values into the formula
an = a1+d(n-1)
7 = a1 + d(10-1)
7 = a1+9d
Now substitute in the equation in which we solved for a1
7 = a1+9d
7 = 32-4d+9d ... replace a1 with 32-4d
7 = 32+5d
5d = 7-32
5d = -25
d = -25/5
d = -5
This tells us that we subtract 5 from each term to get the next term.
Use this d value to find a1
a1 = 32-4d
a1 = 32-4*(-5)
a1 = 32+20
a1 = 52
The first term is 52
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The nth term formula is therefore
an = 52 + (-5)(n-1)
which simplifies to
an = -5n + 57
To check this result, plug in n = 5 to find that a5 = 32. Similarly, you'll find that a10 = 7 after plugging in n = 10. I'll let you do these checks.
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Replace n with 35 to find the 35th term
an = -5n + 57
a35 = -5(35) + 57
a35 = -175 + 57
a35 = -118
143.7 I believe since you take 6.80*20=136+46=2.3*20
136+46=182
182*7.65%=168.08
168.08*8.95%=153.04
153.04*6.1%=143.7
It's not the slope-intercept form of the line.
It's the slope-intercept form of the line's equation.
<em> Y = mX + B</em>
'X' is the slope of the line
'B' is the y-intercept of the line
You can cross multiply to find the answer. Start by setting up your equation:
45/30 = 60/x (30 represents half an hour)
Next, cross multiply, 45 times x, and 60 times 30:
45x = 1800 you must isolate the "x" value by using the opposite operation it is involved in. Here we have 45x (x is multiplied to 45) so we must divide 45, which will cancel itself out, leaving us with "x."
What you do on one side of the equation, you must do on the other, so divide 1800 by 45 as well, which will leave you with 40.
Working it out on paper, your equation should now look like this: x=40, which represents the amount of time it will take to fill a 60 gallon tube.
Answer: It will take 40 minutes to fill a 60 gallon tube.