Question 17
Answer: choice C) y = (x-2)^2 - 3
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Step-by-step explanation:
We know that a = 1 so it matches with the 'a' value in y = x^2. Otherwise, the shapes wouldn't match up and they wouldn't be congruent.
The vertex we want is (h,k) = (2,-3)
Therefore,
y = a(x-h)^2 + k
y = 1(x-2)^2 + (-3)
y = (x-2)^2 - 3
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Question 18
Answer: choice B) min point; -4
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Step-by-step explanation:
The equation y = 3(x-1)^2 - 4 is in the form y = a(x-h)^2 + k which is known as vertex form.
a = 3 being positive tells us the graph opens upward and we have a min point. There is no max point as it goes on forever upward.
The min point is k = -4 which is the y coordinate of the vertex.
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Question 19
Answer: Choice B) y = (1/2)x^2 + 3x - 5
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Step-by-step explanation:
The equation opens up, so the value of 'a' must be positive. This narrows our choices to A or B.
We eliminate choice A because that graph is more narrow compared to y = x^2. Choice B is wider and flatter compared to y = x^2 due to 1/2 being smaller than 1.