Given:
The given equation is:

Where, t is the time in seconds and h is the height of the ball above the ground, measured in feet.
To find:
The inequality to model when the height of the ball is at least 36 feet above the ground. Then find time taken by ball to reach at or above 36 feet.
Solution:
We have,

The height of the ball is at least 36 feet above the ground. It means
.



Splitting the middle term, we get



The critical points are:


These two points divide the number line in 3 intervals
.
Intervals Check point
Result
0
False
4
True
8
False
The inequality is true for (2,6) and the sign of inequality is
. So, the ball is above 36 feet between 2 to 6 seconds.

Therefore, the required inequality is
and the ball is 36 feet above for 4 seconds.
Answer: $12000 was invested at 7% while $8000 was invested at 9%.
Step-by-step explanation:
Based on the information given in the question, let the amount that was invested at 7% be n.
Therefore,
0.07n + 0.09(20000 - n) = 1560
0.07n + 1800 - 0.09n = 1560
-0.02n = 1560 - 1800
-0.02n = -240
n = 240/0.02
n = 120
Therefore, $12000 was invested at 7% while $8000 was invested at 9%.
In order to figure out whether Luis or Isabella skates farther to get to school, we have to create a common denominator between the two fractions that represent the distance that each person walks.
The least common denominator of 3 and 4 is 12. This means that we have to change both fractions into equal fractions with denominators of 12.
To figure this out, we must set up a proportion.
2/3 = x/12
To solve this proportion, we must cross-multiply the fractions. We get:
24 = 3x
If we divide both sides by the coefficient of x which is 3, to get the variable x alone, we get:
x = 8
Therefore, 2/3 = 8/12, so Luis skates 8/12 mile from his home to school.
If we do the same process for the 2/4 mile to get to school for Isabella, we get 6/12, because both fractions are equal to 1/2.
Therefore, we know that Luis skates 8/12 mile to school and Isabella skates 6/12 mile to get to school. Because they have the same denominator, we can just compare the numerators. We know that 8 is greater than 6, thus Luis skates farther to get to school.
Here is the link to the graph. You can scale it and tweak it.
https://www.desmos.com/calculator/mawkflj9ws
Hope this helped!
Answer:
20.
Step-by-step explanation:
That's the correct answer