Answer:
1.703
Step-by-step explanation:
The reason we try to find t score is because the sample size is below 30, meaning the sample size is small
Hence:
Step 1
We find the degree of freedom
The Degrees of freedom = Number of samples - 1
The random number of samples = 28
= 28 - 1
= 27
Step 2
Using a t score table or t score calculator, we can obtain the t score value for a 90% confidence interval and degree of freedom of 27
90% confidence interval =
10% significance level = 0.10 for two tails or 0.1/2 = 0.05 for one tail
Hence: t90 = 1.703
Answer:
A
Step-by-step explanation:
the sum of the two angles is 90 degrees
x + 52 = 90
x = 38 degrees
<em>x = - 2.5</em>
- <em>Step-by-step explanation:</em>
<em>Hi there !</em>
<em>4 - (2x + 4) = 5</em>
<em>4 - 2x - 4 = 5</em>
<em>- 2x = 5</em>
<em>2x = - 5</em>
<em>x = - 5 : 2</em>
<em>x = - 2.5</em>
<em>Good luck !</em>
Answer:
y=-1x+3
Step-by-step explanation:
2-5/1+2
-3/3
-1
y=-1x+b
2=-1+b
b=3
y=-1x+3
The equation gives the height of the ball. That is, h is the height of the ball. t is the time. Since we are looking for the time at which the height is 8 (h=8), we need to set the equation equal to 8 and solve for t. We do this as follows:




This is a quadratic equation and as it is set equal to 0 we can solve it using the quadratic formula. That formula is:

You might recall seeing this as "x=..." but since our equation is in terms of t we use "t-=..."
In order to use the formula we need to identify a, b and c.
a = the coefficient (number in front of)

= 16.
b = the coefficient of t = -60
c = the constant (the number that is by itself) = 7
Substituting these into the quadratic formula gives us:



As we have "plus minus" (this is usually written in symbols with a plus sign over a minus sign) we split the equation in two and obtain:

and

So the height is 8 feet at t = 3.63 and t=.12
It should make sense that there are two times. The ball goes up, reaches it's highest height and then comes back down. As such the height will be 8 at some point on the way up and also at some point on the way down.