9514 1404 393
Answer:
a. 0.6 h
b. 1.3 h
c. C -- No
d. 4.2 mi/h
Step-by-step explanation:
a. The relationship between time (t), speed (s), and distance (d) is ...
t = d/s
The time spent running 4 miles at 7 miles per hour is ...
t = (4 mi)/(7 mi/h) = (4/7) h ≈ 0.6 h
__
b. The time spent walking home is ...
t = (4 mi)/(3 mi/h) = 4/3 h ≈ 1.3 h
__
c. C -- No, less time is spent at 7 mi/h
__
d. The average speed is ...
s = d/t = (4 mi +4 mi)/(4/7 h +4/3 h) = (8 mi)/(40/21 h) = 4.2 mi/h
Here, Twice fast means, she takes half time in doing same amount of work.
Let, Anna takes = 2t & Jane takes = t
It would be: 1/t + 1/2t = 1/15
2t + t / 2t² = 1/15
15(3t) = 2t²
2t² = 45t
Divide both sides by t,
2t = 45
t = 45/2
t = 22.5
& 2t = 22.5(2) = 45
In short, Anna would take 45 minutes
Hope this helps!
Answer:
theyre not because it becomes 32 +x and 37+3x
communitive
distributive
communitive
11x+12
6p+35
2(b+8)+2(3b)
8b+16
perimeter is the length of all sides so it would be b+8 and 3b two times since each side is equal
C
D
Step-by-step explanation:
GIVE ME BRAINLIEST PLS
Answer:
where 
is the number of laptops, and 
is the year.
in 2017: 
Step-by-step explanation:
I will define the variable 
as the number of years that passed since 2007.
Since the school buys 20 lapts each year, after a number of years, the school will have
more laptops.
and thus, since the school starts with 31 laptops, the equation to model this situation is
where is the number of laptops.
since x is the number of years that have passed since 2007, it can be represented like this:
where can be any year, so the equation to model the situation using the year:
and this way we can find the number of laptos at the end of 2017:
and
