Its answer is weak negative
The mistake was in step one when she added the 9 to both sides
x^2 + 8x - 9 = 0
__ + __ = 8 (b)
__ • __ = -9 (a•c)
blanks = -1 and 9
(x - 1)(x + 9)
Solve for x in each one
x = 1 or -9
<h3>
Answer: -2</h3>
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Explanation:
Plug in x = -1 to find that
f(x) = 2|x-1|
f(-1) = 2|-1-1|
f(-1) = 2|-2|
f(-1) = 2*(2)
f(-1) = 4
If you repeat for x = 1, you should find that f(1) = 0
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Now use the average rate of change formula below. Effectively, we're using the slope formula more or less.
The average rate of change on this interval is -2
This is the same as finding the slope through the points (-1, 4) and (1, 0).