1. For the following table of values of a quadratic function, what is the x value of the vertex on the graph?
x y
2 5
4 2
6 2
8 5
answer: either 1.5, 5, 2, none
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Use the discriminant to tell whether or not the indicated function ever has the given values of y for real values of x.
y = 5x^2 - 8x + 6
y=3
a. yes
b. no
c. not enough information
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State the complex conjugate of
4 - 5i
a. -4+5i
b. 4+5i
c. 5-4i
d. -5+4i
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How many x intercepts does the graph
y = 2x^2 - 20x + 50
a. 2
b. 1
c. 0
d.not enough information
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Choose the correct values of a, b, and c in the equation
0 = 3x^2 + 2x - 1
a. a=0, b=3, c=2
b. a=3, b=2, c=-1
c. a=-1, b=2. c=3
d. a=1, b=0, c=-1
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For the following quadratic equation,
y = x^2 + 8x - 32
Find the y intercept
a. 8
b. 16
c. -32
d. 0
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thank you!
+23254 Question #1: Since you have the two points (4,2) and (6,2) that have the same height (the same y-value), the vertex will have an x-value halfway between the x-values of these points.
Question #2: Substituting y = 3 into the equations y = 5x² - 8x + 6 gives you: 3 = 5x² - 8x + 6 ---> 0 = 5x² - 8x + 3. Now use the discriminant: b² - 4ac to get your answer (If the value is zero or positive, your answer is 'yes'; if negative, your answer is 'no').
Question #3: The complex conjugate of a + bi is a - bi (and vice versa).
Question #4: Find the discriminant of this function; if the discriminant is positive, you have two x-intercepts; if the discriminant is zero, you have one x-intercept; if the discriminant is negative, you have no x-intercepts.
Question #4: The form is ax² + bx + c. Compare the problem to this form and pick out the values for a, b, and c.
Question #5: Replace x with zero and calculate the value.
+23254 Question #1: Since you have the two points (4,2) and (6,2) that have the same height (the same y-value), the vertex will have an x-value halfway between the x-values of these points.
Question #2: Substituting y = 3 into the equations y = 5x² - 8x + 6 gives you: 3 = 5x² - 8x + 6 ---> 0 = 5x² - 8x + 3. Now use the discriminant: b² - 4ac to get your answer (If the value is zero or positive, your answer is 'yes'; if negative, your answer is 'no').
Question #3: The complex conjugate of a + bi is a - bi (and vice versa).
Question #4: Find the discriminant of this function; if the discriminant is positive, you have two x-intercepts; if the discriminant is zero, you have one x-intercept; if the discriminant is negative, you have no x-intercepts.
Question #4: The form is ax² + bx + c. Compare the problem to this form and pick out the values for a, b, and c.
Question #5: Replace x with zero and calculate the value.
