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2 years ago

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The number of cases of a new disease can be modeled by the quadratic regression equation y = –2x2 + 36x + 6, where x represents

the year. Which is the best prediction for the number of new cases in year 15? A. 194 B. 96 C. 328 D. 614

1 answer:

Helen [10]2 years ago

5 0

y = –2x^2 + 36x + 6

x=15

y = -2*15^2 +36(15) +6

y= -2(225) +540+6

y=-450+540+6

y=96

Answer: Choice B

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The traffic-control monitor on the freeway shows 200 vehicles per minute passing the camera in 5 minutes. Of those vehicles, on

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2 years ago

A bench is located where the shadows casted by a 16 foot tall flagpole and 40-foot tall tree meet. If the bench is 18 feet from

saveliy_v [14]

Answer:

<em>The distance from the flagpole to the tree is 27 ft</em>

Step-by-step explanation:

<u>Similar Triangles</u>

Since the elevation angle from which the trees cast their shadows has the same measure and given the tree and the flagpole and the ground form right angles, both triangles are similar.

Similar triangles have their corresponding side lengths proportional. The ratio between the distances from the bench to the tree and flagpole and their heights is constant, i.e.:

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Where x is the distance from the bench to the tree.

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2 years ago

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stiv31 [10]

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2 years ago

can anyone help me with these? I'm having a lot of trouble and I'm extremely behind... I need to catch up badly!!! i have been a

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Answer:

Step-by-step explanation:

5 and 6 are the same, so I will do one of those and you can use the example to do the other one.

Slope-intercept form is y = mx + b. If we have 2 points and nothing else, we can use those 2 points in the slope formula to find the slope (the m value in the equation) and then plug that in with either one of the points to get the equation. The slope formula is:

$m=\frac{y_{2} -y_{1} }{x_{2}-x_{1} }$

Using our points in question 5: (2, 4) (5, 4)

$m=\frac{4-4}{5-2} =\frac{0}{3}=0$ So m = 0. Now pick a point and use it in the equation along with the m value to solve for b. I will use (2, 4):

4 = 0(2)+b and

4 = 0 + b so

b = 4.

Now we have m = 0 and b = 4 so we fill in the equation with that info:

y = 0x + 4 or simplifying,

y = 4

For question 7 they want the line parallel to y = 3x + 6 that goes through (-10, 2.5). For a line to be parallel to another line, their slopes have to be identical. The slope in y = 3x + 6 is 3. So the slope of the "new" line is going to be 3 as well. Now we will use that slope and the given point to solve for b, just like in #5:

2.5 = 3(-10) + b and

2.5 = -30 + b so

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Now we will fill in:

y = 3x + 32.5

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-11 = -4 + b so

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$y=\frac{1}{4}x-7$

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x + 4y = 6, then

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$y=-\frac{1}{4}x+\frac{3}{2}$

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$5=(-\frac{1}{4})(-8)+b$ which simplifies to

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<span>Semicircle area = circle area / 2 = (pi*r^2)/2 16 in is the radius. Let's call the area of this semicircle s. 3.14*16^2=s

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</span>
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2 years ago

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