Answer:
7.5cm²
Complete question:What is the surface area of the 8-sided figure?
Step-by-step explanation:
Consider the half of the 8-sided die i.e the pyramid ABCDE:
As the base is 6 of the perimeter, so each side of the base is 6/4=3/2
Now, the distance between the tallest points is 2 cm, so the height of Pyramid ABCDE is 1 cm.
Considering the right triangle EOM:
EO=1, OM= 3/4 (it is half of AB=3/2) and EM is the hypothenuse, so by the pythagorean theorem length of EM is
![\sqrt{1+ ( \frac{3}{4} )^{2} }= \sqrt{1+ \frac{9}{16} }= \sqrt{ \frac{25}{16} }= \frac{5}{4} (cm)](https://tex.z-dn.net/?f=%5Csqrt%7B1%2B%20%28%20%5Cfrac%7B3%7D%7B4%7D%20%29%5E%7B2%7D%20%7D%3D%20%20%5Csqrt%7B1%2B%20%5Cfrac%7B9%7D%7B16%7D%20%7D%3D%20%5Csqrt%7B%20%5Cfrac%7B25%7D%7B16%7D%20%7D%3D%20%5Cfrac%7B5%7D%7B4%7D%20%20%20%28cm%29)
5. So side EBC has area
![\frac{1}{2}BC*EM= \frac{1}{2}* \frac{3}{2}* \frac{5}{4}= \frac{15}{16}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B2%7DBC%2AEM%3D%20%20%5Cfrac%7B1%7D%7B2%7D%2A%20%5Cfrac%7B3%7D%7B2%7D%2A%20%5Cfrac%7B5%7D%7B4%7D%3D%20%5Cfrac%7B15%7D%7B16%7D)
6. The total area is 8*Area(EBC)=![8* \frac{15}{16}= \frac{15}{2}=7.5 ( cm^{2} )](https://tex.z-dn.net/?f=8%2A%20%5Cfrac%7B15%7D%7B16%7D%3D%20%5Cfrac%7B15%7D%7B2%7D%3D7.5%20%28%20cm%5E%7B2%7D%20%29)
The truck was going 40 miles per hour
The amount of time was 2 hours:
(90-80: 10)(10/2=5)
80 divided by two is 40
The car was going 45 miles per hour
(90-80:10)(10/2=5)
90 divided by two is 45
Hopefully you find this helpful
Answer:
3 1/2 cups
Step-by-step explanation:
24=2
42=x
24x=84
/24 /24
3.5