Answer:
x=54
Step-by-step explanation:
Step-by-step explanation:
1. The equation graph is a parabola, so the maximum height will be the vertex of the parabola. You can find the vertex coordinate t using the formula:
t = -b/2a
t = -18/2•(-4.9)
t = -18/-9.8
t = 1.84 seconds
2. The height of the ground is 0, so the balls hit the ground when the equation result is 0:
0 = -4.9t²+18t+10
Now you solve it using Bhaskara:
Δ = b² -4ac
Δ = 18² -4•(-4.9)•10
Δ = 520
t = (-b ±√Δ)/2a
t = (-18 ± √520)/2•(-4.9)
t1 = (-18 - 20.8)/-9.8
t1 = 3.96 seconds
t2 = (-18 +20.8)/-9.8
t2 = -0.28
Doesn't exist negative time, so we pick the first value found, t = 3.96 seconds
3. Now you just need to put 3 in place of t to find the result:
h = -4.9•3² +18•3 +10
h = -4.9•9 + 54 + 10
h = -44.1 + 64
h = 19.9 meters
4. You just need to put 1 in place of t to find the height:
h = -4.9•1²+12
h = -4.9+12
h = 7.1 meters
Answer:
Step-by-step explanation:
We are given the following in the question:
Sample size, n = 64
Sample mean = 22.3
Sample standard deviation = 8.8
We want to estimate 92% confidence interval.
92% Confidence interval:
Putting the values, we get,
Degree of freedom = n - 1 = 63
so get the people down to unit rates first
Natalie= 40 in 9 minutes
Steven= 10 in 3 minutes
multiply Stevens to get it even
so by 3
30 in 9 minutes
so Natalie paints faster
hope I was helpful
Given:
speed = distance / time
walking: 3 miles per hour
running 5 miles per hour
for a total of 3 hours.
3t = 5(3-t)
3t = 15 - 5t
3t + 5t = 15
8t = 15
t = 15/8
t = 1 7/8
7/8 * 60 mins = 52.50 minutes
t = 1 hour and 52.5 minutes
It took Stu 1 hour and 52.5 minutes to hike the trail one way.