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
Step-by-step explanation:
The population of a small town is 1600 and is increasing at a rate or. 3% per year.
Answer:
- m = (2-(-2))/(2-(-2)) = 4/4 = 1
- y +2 = 1(x +2)
Step-by-step explanation:
The point-slope form of the equation for a line with slope m through point (x1, y1) is ...
y -y1 = m(x -x1)
To find the slope of the line, find the ratio of the difference in y-values of the points to the difference in corresponding x-values. Here, the slope is ...
m = (2 -(-2))/(2 -(-2)) = 4/4 = 1 . . . work to compute slope
The problem statement tells you x1 = -2, y1 = -2. Putting the numbers in to the point-slope form gives ...
y -(-2) = 1(x -(-2))
y + 2 = x + 2 . . . equation form with m, (x1, y1) filled in
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The answer at the top leaves the slope shown as 1. We don't know how much simplification you are expected to do. Obviously, this <em>could</em> be simplified to y=x, but then the use of (-2, -2) for the point would not be obvious.
Answer:
sin θ . tan θ
Step-by-step explanation:
Note : -
sec ( - θ ) = sec θ
Formula / Identity : -
sec θ = 1 / cos θ
sec ( - θ ) - cos θ
= [ 1 / cos θ ] - cos θ
{ LCM = cos θ }
= [ 1 / cos θ ] - [ cos²θ / cos θ ]
= [ 1 - cos²θ ] / cos θ
{ 1 - cos²θ = sin²θ }
= sin²θ / cos θ
{ sin²θ = sin θ . sin θ }
= sin θ . sin θ / cos θ
{ sin θ / cos θ = tan θ }
= sin θ . tan θ
Hence, simplified.
