Answer:
a.(-b) ( third choice)
explanation:
-a+b - there is no plus sign for -a.b.
not -a+b
(-a)(-6)=6a (-negative sign and -negative sign=+positive sign)
If you are working with time or days, you can't put in a negative value because if you are doing an experiment, you can't go back in time to do that experiment to gather data. (Time for the most part considered to be an input value so that's why I used it as an example.)
Answer:
A. b(w) = 80w +30
B. input: weeks; output: flowers that bloomed
C. 2830
Step-by-step explanation:
<h3>Part A:</h3>
For f(s) = 2s +30, and s(w) = 40w, the composite function f(s(w)) is ...
b(w) = f(s(w)) = 2(40w) +30
b(w) = 80w +30 . . . . . . blooms over w weeks
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<h3>Part B:</h3>
The input units of f(s) are <em>seeds</em>. The output units are <em>flowers</em>.
The input units of s(w) are <em>weeks</em>. The output units are <em>seeds</em>.
Then the function b(w) above has input units of <em>weeks</em>, and output units of <em>flowers</em> (blooms).
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<h3>Part C:</h3>
For 35 weeks, the number of flowers that bloomed is ...
b(35) = 80(35) +30 = 2830 . . . . flowers bloomed over 35 weeks
Answer:
1 1/3 hours
Step-by-step explanation:
Pipe 1 alone:
fills the pool in 2 hours
in 1 hour, it fills 1/2 of the pool
Pipe 2 alone:
fills the pool in 4 hours
in 1 hour, it fills 1/4 of the pool
Pipe 1 and Pipe 2 working together:
fill the pool in x hours
in 1 hour, they fill 1/x of the pool
Working together, in 1 hour the two pipes fill 1/2 + 1/4 of the pool.
Working together, in 1 hour the two pipes fill 1/x of the pool.
Therefore,
1/2 + 1/4 = 1/x
2/4 + 1/4 = 1/x
3/4 = 1/x
x = 4/3
x = 1 1/3
Answer: 1 1/3 hours