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
The y intercept is 1.5x+22.7 + the linear equation which is 22
They ate 2/3 together. And, they have 1/3 left!
Explanation:
Conversion of a quadratic equation from standard form to vertex form is done by completing the square method.
Assume the quadratic equation to be 
where x is the variable.
Completing the square method is as follows:
- send the constant term to other side of equal
- divide the whole equation be coefficient of
, this will give 
- add
to both side of equality 
- Make one fraction on the right side and compress the expression on the left side
- rearrange the terms will give the vertex form of standard quadratic equation
Follow the above procedure will give the vertex form.
(NOTE : you must know that 
. Use this equation in transforming the equation from step 3 to step 4)
The general form of the equation we need to find is (x - h)^2 = 4p(y- k).
The center is the distance between the directrix and focus.
So, center (h, k) = (3, 3/2) .
P = distance from center to the focus and it just so happens to be 1.5.
We now plug everything into the formula given above.
(x - 3)^2 = 4(1.5)(y - 3/2)
(x - 3)^2 = 6(y - 3/2)
Done!
