Question

Substitute the values for a, b, and c into b2 – 4ac to determine the discriminant. Which quadratic equations will have two real number solutions? (The related quadratic function will have two x-intercepts.) Check all that apply. 0 = 2x2 – 7x – 9 0 = x2 – 4x + 4 0 = 4x2 – 3x – 1 0 = x2 – 2x – 8 0 = 3x2 + 5x + 3

Answer 1

Answer:

A, C, D

Step-by-step explanation:

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Answer 2

Step-by-step explanation

Prerequisites:

You need to know:

$b^2 - 4ac = 0 \Rightarrow 1 solution$

$b^2 - 4ac > 0 \Rightarrow 2 solutions$

$b^2 - 4ac < 0 \Rightarrow No\ real\ solutions$

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$2x^2-7x-9 = 0$

$b^2 - 4ac$

$-7^2 - 4(2)(-9) = 121$

2 Solutions

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$x^2-4x+4 = 0$

$b^2 - 4ac$

$-4^2 - 4(1)(4) = 0$

1 Solution

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$4x^2-3x-1 = 0$

$b^2 - 4ac$

$-3^2 - 4(4)(-1) = 25$

2 Solutions

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$x^2-2x-8 = 0$

$b^2 - 4ac$

$-2^2 - 4(1)(-8) = 36$

2 Solutions

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$3x^2+5x+3 = 0$

$b^2 - 4ac$

$5^2 - 4(3)(3) = -11$

No Solutions

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