Find the zeros of y=x2-4x-9 by completing the square
1 answer:
Answer:
x = 2 ±
Step-by-step explanation:
To find the zeros let y = 0, that is
x² - 4x - 9 = 0 ( add 9 to both sides )
x² - 4x = 9
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(- 2) x + 4 = 9 + 4
(x - 2)² = 13 ← take the square root of both sides
x - 2 = ± ← add 2 to both sides
x = 2 ±
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Based on the table, a conclusion which can be drawn about f(x) and g(x) is that: B. the functions f(x) and g(x) are reflections over the y-axis.
<h3>How to compare the functions f(x) and g(x)?</h3>In Mathematics, two functions are considered to be reflections over the y-axis under the following condition:
If, f(-x) = g(x).
Evaluating the given functions, we have:
f(x) = 2ˣ
f(-x) = 2⁻ˣ = ½ˣ = g(x).
Similarly, two functions are considered to be reflections over the x-axis under the following condition:
If, -f(x) = g(x).
Evaluating the given functions, we have:
f(x) = 2ˣ
-f(x) = -2ˣ ≠ g(x).
Therefore, we can logically conclude that the two functions f(x) and g(x) are considered to be reflections over the y-axis but not the x-axis.
Read more on reflections here: brainly.com/question/2702511
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