A firecracker shoots up from a hill 145 feet high, with an initial speed of 80 feet per second. Using the formula H(t) = −16t2 + vt + s, approximately how long will it take the firecracker to hit the ground?13 seconds
11 seconds
Nine seconds
Six seconds
Answers
0 = -16t^2 + 80t + 145
This a quadratic equation with two roots. Solving it using using the quadratic formula or by factoring, or by any other solution, the roots are:
6.4531 and -1.4131
We are dealing with time, so we choose the positive root.
Therefore, the answer is 6.4531 seconds
Answer:
6 seconds
Step-by-step explanation:
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How many seconds in 10 minutes??
Yuto and Riko went for a bike ride on the same path. When Riko left their house, Yuto was 5.25 miles along the path. If Yuto’s average speed was 0.25 miles per minute and Riko’s average speed was 0.35 miles per minute, then Riko will be behind Yuto when 0 ≤ t < 52.5, where t is time in minutes. Explain what this solution means and why t cannot be less than zero.
Answers
Answer: 0.621%
Step-by-step explanation:
Answers
1. $322.90 - rounded to the 2nd decimal place.
2. 79667 - rounded to whole number.
3. $2400
Hope this helps! If you want to know how to figure them out just contact me by leaving a comment.
Jimmy2003
Answers
Final answer:
The problem involves finding the side length of a square field given its area. The side length is found by taking the square root of the area. Rounded to the nearest foot, the side length is approximately 22 feet.
Explanation:
The subject here is Mathematics, specifically focusing on geometry. More specifically, the problem is addressing the characteristics of square fields. A square is a shape which has all sides equal in length. The area of a square is calculated by squaring the length of one side (i.e., side * side) or more visually demonstrated as side2.
Given that the area of the square is 479 square feet, you need to find the length of one side. To do this, you would take the square root of the area, because the area of a square field is side2.
Mathematically expressed, this would be:
- Side length = √Area
- Side length = √479
Using a calculator, you will find the square root of 479 is approximately 21.89. We are asked to give the answer to the nearest foot, so you would round 21.89 to the nearest whole number to get 22 feet. Therefore, the approximate length of a side of the field is 22 feet.
Learn more about Square root here:
#SPJ2
Answers
Answer:
A B
Additive Identity (x) x + 0 = x
Additive Inverse (x) b + (-b) = 0
Multiplicative Identity (x) x • 1 = x
Multiplicative Inverse (x) x • (1/x) = 1
4+3x=5
What is X?
Answers
Subtract 4 from each side:
3x = 1
Divide each side by 3 :
x = 1/3
13.5, 12.2, 12.8, 12.8, 12.3, 12, 13.9, 14, 14.2, 12.6
Jack made the following box plot to represent the heights:
box plot shows minimum at 12, first quartile at 12.5, median at 12.8, third quartile at approximately 13.9 and maximum at 14.2
Which of the following did Jack show incorrectly on his box plot?
Median
Minimum
First quartile
Third quartile
Answers
Answer:
The First Quartile is incorrect.
Step-by-step explanation:
Step 1: Order the Numbers
They should looks like this: 12 12.2 12.3 12.6 12.8 12.8 13.5 13.9 14 14.2
Step 2: Find the Median
Since there is an even amount of numbers (10), the median is the sum of the two middle numbers divided by two: 12.8 + 12.8 = 25.6, 25.6 ÷ 2 = 12.8. So, 12.8 is our Median. Since our next steps will involve us figuring out more Medians, we will call this the "original Median." (I would suggest you replace the two numbers with one 12.8 and circle it so you know that this is the Median.)
Step 3: Find the Median for the Quartiles
Now you need to find the Median for the numbers leading up to the "original" Median and the numbers following the "original" Median. Since there is again, an even amount of numbers (4), you will add the two middle numbers of those four and divide the sum. Leading up to the Median: 12.2 + 12.3 = 24.5, 24.5 ÷ 2 = 12.25 (First Quartile). Following the Median: 13.9 + 14 = 27.9, 27.9 ÷ 2 = 13.95 (Second Quartile). (Again, I would suggest you replace each two numbers with the one median and circle it so that you will know that these will be the end of your first and third quartiles.)
Step 4: Find the Quartiles
Referring to Jack's Box Plot, the end of his line should start at 12 (that is the lowest number) and should end at 14.2 (that is the highest number). The "original Median" is 12.8, which will be the line inside of his box. Since we figured out what the median is leading up to the "original Median", his box should start at 12.25, and since we figured out the Median following the "original Median" we know that his box should end at 13.95.
Step 5: Make sure they match up
Let's organize this a bit better; numbers 12 - 12.25 (first quartile), 12.25 - 12.8 (second quartile), 12.8 - 13.95 (third quartile), 13.95 - 14.2 (fourth quartile). All of these match correctly except for our first quartile. It starts correctly at 12 but does not end at 12.25 and instead ends around 12.5.
Incorrect: First Quartile
After working out the problem and figuring out what Jack did wrong, we now know that Jack incorrectly worked the First Quartile.
Hope this helped and that it wasn't too confusing. Also, if it was too confusing, try reading it and working out the problem yourself as you read the steps. :)