Answer:
t=0.64
Step-by-step explanation:
h = -16t^2 +4t +4
We want h =0 since it is hitting the ground
0 = -16t^2 +4t +4
Using the quadratic formula
a = -16 b = 4 c=4
-b ± sqrt( b^2 -4ac)
----------------------------
2a
-4 ± sqrt( 4^2 -4(-16)4)
----------------------------
2(-16)
-4 ± sqrt( 16+ 256)
----------------------------
-32
-4 ± sqrt( 272)
----------------------------
-32
-4 ± sqrt( 16*17)
----------------------------
-32
-4 ± sqrt( 16) sqrt(17)
----------------------------
-32
-4 ± 4 sqrt(17)
----------------------------
-32
Divide by -4
1 ± sqrt(17)
----------------------------
8
To the nearest hundredth
t=-0.39
t=0.64
Since time cannot be negative
t=0.64
9514 1404 393
Answer:
64.6
Step-by-step explanation:
One standard deviation is 4.3. Then +2 standard deviations is ...
(+2)(4.3) = +8.6
This amount added to the mean gives ...
56 +8.6 = 64.6 . . . . +2σ from the mean
Answer:
Step-by-step explanation:
The formula for determining the confidence interval for the difference of two population means is expressed as
Confidence interval = (x1 - x2) ± z√(s²/n1 + s2²/n2)
Where
x1 = mean sale amount for mail order sales = 82.70
x2 = mean sale amount for internet sales = 66.9
s1 = sample standard deviation for mail order sales = 16.25
s2 = sample standard deviation for internet sales = 20.25
n1 = number of mail order sales = 17
n2 = number of internet sales = 10
For a 99% confidence interval, we would determine the z score from the t distribution table because the number of samples are small
Degree of freedom =
(n1 - 1) + (n2 - 1) = (17 - 1) + (10 - 1) = 25
z = 2.787
Margin of error =
z√(s²/n1 + s2²/n2) = 2.787√(16.25²/17 + 20.25²/10) = 20.956190
The solution of the equation is x = -4/3.
<h3>What does it mean to solve an equation?</h3>
An equation represents equality of two or more mathematical expression.
Solutions to an equation are those values of the variables involved in that equation for which the equation is true.
WE have been given an equation as;
|x - 4| = 5x + 12
In an absolute value equation, we solve the original expression as our first equation. Our second one is that we multiply the right side by -1.
Case 1: original equation
|x - 4| = 5x + 12
x - 4 = 5x + 12
x - 5x = 12 + 4
-4x = 16
x = -4
Case 2: Opposite equation
|x - 4| = 5x + 12
x - 4 = - (5x + 12)
x - 4 = - 5x - 12
x + 5x = -12 + 4
6x = -8
x = -4/3
Now we have two solutions. We need to check for extraneous solutions because of all the manipulations;
Check:
|x - 4| = 5x + 12
use x = -4
|-4 - 4| = 5(-4) + 12
| -8 | = -20 + 12
8 = -8
Thus, it is Not a solution
Now, |x - 4| = 5x + 12
use x = -4/3
| -4/3 - 4| = 5( -4/3) + 12
|-16/3 | = -20/3 + 12
|-16/3 | = 16/3
16/3 = 16/3
Thus, it is the Solution.
Learn more about solving equations here:
brainly.com/question/18015090
#SPJ1
Answer:
(6y-3)/7
Step-by-step explanation:
(2y-1/y²)(3y²/7) first simplify 3y²/y² =3
(2y-1)(3/7) =
(6y-3)/7
