Answer:
O 68, 14, 3
Step-by-step explanation:
Given:
f(x) = 4x² - x
When x = -4
f(x) = 4x² - x
= 4(-4)² - (-4)
= 4(16) + 4
= 64 + 4
f(x) = 68
When x = 1
f(x) = 4x² - x
= 4(1)² - 1
= 4(1) - 1
= 4 - 1
f(x) = 3
When x = 2
f(x) = 4x² - x
= 4(2)² - 2
= 4(4) - 2
= 16 - 2
f(x) = 14
The answer = 68, 3, 14
first we change the format: y=-3x-5 Since its perpendicular the slope will be a negative inverse. y=mx+b
<h3>
Answer: D) h(x) = (1/4)x</h3>
This is the same as h(x) = x/4
In decimal form, it would be h(x) = 0.25x
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Explanation:
Inverses undo the original function. The original function tells us to take any input (x) and multiply by 4 to get the output y = f(x) = 4x
To get the inverse, we reverse the operation applied here. The opposite of multiplication is division. So we'll divide by 4 instead of multiply by 4. This is why the answer is x/4 or (1/4)x
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Another approach is to do the following: Replace f(x) with y. Swap x and y. Solve for y
f(x) = 4x
y = 4x
x = 4y
4y = x
y = x/4
h(x) = x/4
We end up with the same result as before.
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Extra info:
For any real number x, the following two equations are true
h( f(x) ) = x
f( h(x) ) = x
They will require between 18.42 and 31.58 minutes.
We want the middle 90%. The two probability values associated with this would be 0.95 and 0.05; this would leave 5% below and 5% above, giving us the middle 90%.
Using a z-table (http://www.z-table.com) we see that the z-score associated with an area to the left of 0.05 is between -1.64 and -1.65; since it is equally distant from both we will use -1.645.
The z-score associated with an area of the left of 0.95 is between 1.64 and 1.65; since it is equally distant from both we will use 1.645.
The formula for a z-score is
z = (X-μ)/σ
-1.645 = (X-25)/4
Multiplying by 4 on both sides,
-1.645(4) = X-25
-6.58 = X-25
Adding 25 to both sides,
-6.58+25 = X
18.42 = X
For the upper bound,
1.645 = (X-25)/4
Multiplying both sides by 4,
1.645(4) = X-25
6.58 = X-25
Adding 25 to both sides,
6.58+25 = X
31.58 = X
The times are between 18.42 and 31.58 minutes.