Answer:
![28 cm^2](https://tex.z-dn.net/?f=28%20cm%5E2)
Step-by-step explanation:
<em><u>The formula for finding the area of a triangle is:</u></em>
<em><u /></em>![\frac{1}{2} bh](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D%20bh)
<em><u>The "b," is the base (7), and the "h," is the height (8):</u></em>
![\frac{1}{2} (7)(8)](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D%20%287%29%288%29)
![\frac{1}{2} (56)](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7D%20%2856%29)
28
Answer:
(53.812 ; 58.188) ; 156
Step-by-step explanation:
Given that :
Sample size (n) = 51
Mean (m) = 56
Standard deviation (σ) = 9.5
α = 90%
Using the relation :
Confidence interval = mean ± Error
Error = Zcritical * (standard deviation / sqrt (n))
Zcritical at 90% = 1.645
Error = 1.645 * (9.5 / sqrt(51))
Error = 1.645 * 1.3302660
Error = 2.1882877
Hence,
Confidence interval :
Lower boundary = 56 - 2.1882877 = 53.8117123
Upper boundary = 56 + 2.1882877 = 58.1882877
Confidence interval = (53.812 ; 58.188)
2.)
Margin of Error (ME) = 1.25
α = 90%
Sample size = ((Zcritical * σ) / ME)^2
Zcritical at 90% = 1.645
Sample size = ((1.645 * 9.5) / 1.25)^2
Sample size = (15.6275 / 1.25)^2
Sample size = 12.502^2 = 156.3000
Sample size = 156
Answer:
<em>(C).</em> <em>(t² - p)( </em>
<em> + pt² + p²) </em>
Step-by-step explanation:
a³ - b³ = (a - b)(a² + ab + b²)
- p³ = (t²)³ - p³ = <em>(t² - p)( </em>
<em> + pt² + p²)</em>
Answer:
time = distance/speed
3080/770 = 4
So it took 4 hours.
Step-by-step explanation:
The measure of ∠4 is 45°.
Solution:
Line segment VR is parallel to the line segment US.
m∠1 = 45°
∠1 and ∠4 are corresponding angles.
<em>If two lines are parallel, then the corresponding angles are congruent.</em>
m∠1 = m∠4
45° = m∠4
m∠4 = 45°
The measure of ∠4 is 45°.