Answer:
umm gotta be specific how long is the frame?
Step-by-step explanation:
In accordance with the function <em>velocity</em>, the car will have a complete stop after 6 seconds.
<h3>When does the car stop?</h3>
Herein we have a function of the velocity of a car (v), in feet per second, in terms of time (t), in seconds. The car stops for t > 0 and v = 0, then we have the following expression:
0.5 · t² - 10.5 · t + 45 = 0
t² - 21 · t + 90 = 0
By the <em>quadratic</em> formula we get the following two roots: t₁ = 15, t₂ = 6. The <em>stopping</em> time is the <em>least</em> root of the <em>quadratic</em> equation, that is, the car will have a complete stop after 6 seconds.
To learn more on quadratic equations: brainly.com/question/2263981
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Answer:
a) 20.16; b) 20.49 and 21.51
Step-by-step explanation:
We use z scores for each of these. The formula for a z score is
.
For part a, we want the 20th percentile; this means we want 20% of the data to be lower than this. We find the value in the cells of the z table that are the closest to 0.20 as we can get; this is 0.2005, which corresponds with a z score of -0.84.
Using this, 21 as the mean and 1 as the standard deviation,
-0.84 = (X-21)/1
-0.84 = X-21
Add 21 to each side:
-0.84+21 = X-21+21
20.16 = X
For part b, we want the middle 39%. This means we want 39/2 = 19.5% above the mean and 19.5% below the mean; this means we want
50-19.5 = 30.5% = 0.305 and
50+19.5 = 69.5% = 0.695.
Looking these values up in the cells of the z table, we find those exact values; 0.305 corresponds with z = -0.51 and 0.695 corresponds with z = 0.51:
-0.51 = (X-21)/1
-0.51 = X-21
Add 21 to each side:
-0.51+21 = X-21+21
20.49 = X
0.51 = (X-21)/1
0.51 = X-21
Add 21 to each side:
0.51+21 = X-21+21
21.51 = X
3. The simplest form of √42 is √42
4. √75
Rewrite 75 as 5^2 * 3
Now you have √(5^2*3)
Pull squared terms out from the radical to get 5√3
Firstly, you have to count the number of spaces between the two points on the line, which gives you 9. Now, remember that you are counting between tenths on a number line, so you divide 9 by 10 to give you your answer, 0.9.