The vertex is the high point of the curve, (2, 1). The vertex form of the equation for a parabola is
.. y = a*(x -h)^2 +k . . . . . . . for vertex = (h, k)
Using the vertex coordinates we read from the graph, the equation is
.. y = a*(x -2)^2 +1
We need to find the value of "a". We can do that by using any (x, y) value that we know (other than the vertex), for example (1, 0).
.. 0 = a*(1 -2)^2 +1
.. 0 = a*1 +1
.. -1 = a
Now we know the equation is
.. y = -(x -2)^2 +1
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If we like, we can expand it to
.. y = -(x^2 -4x +4) +1
.. y = -x^2 +4x -3
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An alternative approach would be to make use of the zeros. You can read the x-intercepts from the graph as x=1 and x=3. Then you can write the equation as
.. y = a*(x -1)*(x -3)
Once again, you need to find the value of "a" using some other point on the graph. The vertex (x, y) = (2, 1) is one such point. Subsituting those values, we get
.. 1 = a*(2 -1)*(2 -3) = a*1*-1 = -a
.. -1 = a
Then the equation of the graph can be written as
.. y = -(x -1)(x -3)
In expanded form, this is
.. y = -(x^2 -4x +3)
.. y = -x^2 +4x -3 . . . . . . same as above
Answer:
21
Step-by-step explanation:
- AC = 64
- AB = 7x + 8
- BC = 3x + 6
<u>Since AC = AB + BC</u>
- 7x + 8 + 3x + 6 = 64
- 10x + 14 = 64
- 10x = 50
- x = 50/10
- x = 5
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BC = 3x + 6 = 3*5 + 6 = 21
Answer:
(C) Sample: the 120 students surveyed. Population: the 1200 students at the high school. Parameter of interest: the average number of hours a student at this high school sleeps per night.
Step-by-step explanation:
The correct answer is (C). The sample is a subset of the population, and the parameter is a characteristic of the population of interest.
Idk
At least 20 characters to explain it well.
If the -8 is under the square root, then...
OR
If the -8 is not under the square root, then...
Either way, we replace x with -3 and simplify.
For more information, refer to the direct substitution rule for limits.
