Answer:
<u><em>y = -190 cos(π t / 120) + 195</em></u>
Step-by-step explanation:
<em>General form of a sinusoidal function: y = A cos(Bt - C) + D
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<em>Now generally a cosine function starts at the maximum value, so to start at the minimum value, flip the cosine function by making it negative.
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<em>A is the amplitude of the curve and will be the radius of the ferris wheel. Therefore, A = 380 / 2 = 190 feet.
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2π / B is the period of the curve and will be the time to complete one full rotation. The time to complete one full rotation is given as 4 minutes. Convert this into seconds to get period = 4 minutes * (60 seconds / minute) = 240 seconds. Therefore, B = 2π / period = 2π / 240 seconds = π / 120.
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C/B is the phase shift, or horizontal shift of the graph. Since the negative cosine function already starts at the minimum value, there is no phase shift so C/B = 0, meaning C = 0.
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D is the vertical shift and will be the height of the center of the ferris wheel. Therefore, D = 195 feet.
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Your final function will be:</em>
<u><em>y = -190 cos(π t / 120) + 195</em></u>
The correct answer is A: x=2 and y=-3. Either method would work, but for example, let's use elimination. If you multiply the second equation by 5, you get: 10x +5y = 5. When you add both equations, you can then cross out both y terms. You are left with one equation that reads: 13x=26. Solving for x gives you 2. You can substitute 2 in for x in either equation and you will receive -3 for your y value.
Equation in point slope form of a line:
y-y₀=m(x-x₀)
m=slope
(x₀,y₀)=(-4,7)
m=2/3
y-7=(2/3)(x+4)
Answer: y-7=(2/3)(x+4)
It's 2/5 in decimal form it is 0.4.
The answer is b I’m pretty sure
