Answer:
-13b
Step-by-step explanation:
(2b^2 - 5b) - (7b + 3b^2)
-3b^2 - 10b^2 = -13b
B- 40 hours because 4/20 = 0.2 and 0.2*200=40
Answer:
I think it is the second one.
Step-by-step explanation:
It might be right.
Hope this helps! :)
Answer:
4 hours
Step-by-step explanation:
We can already assume that the freight train is 60 miles ahead of the express. If the freight is going at a constant of 30 mph and the express goes 50 mph then we can say that when the freight train has been gone for 6 and the express for 4 the express will have passed the freight. The reason as to why would be that 60 + 120 = 180 or 60 + (30 x 4) = 180 and 50 x 4 = 200 .
Sorry if that explanation doesn't make sense but I hope this helped.
7.
assuming you mean SURFACE area
look at shape
fold it out or whateveryo yo like
we see that the faces are
4 triangles
4 rectangles in midddle
4 more triangles on other side
calculate areas
area of triangle=1/2bh
area of rectangle=bh
leftmost side
h=1.8
b=2
4*1/2*2*1.8=7.2 cm^2
middle recangles
base=3
height=2
aera=3*2=6
multply by 4 snce 4 recangles
6*4=24 cm^2
other triangles
b=2
h=2.71
total area=4*1/2*2*2.71=10.84cm^2
add them up
7.2cm^2+24cm^2+10.84cm^2=42.04cm^2
8. interesting question, not enought time to answer for me and partially too copmplex
