The value of f(5) is 
Step-by-step explanation:
The function is 
To find
substitute
in 

Multiplying the terms, we get,

Adding the terms, we get,

Thus, the value of
is 
Answer:
I believe it would be 21 units . dont let extra line's confuse you just pay attention to the letters its asking for
Answer:
Step-by-step explanation:
let the speed of one plane=x
speed of other plane=x+80
time=4 hrs
then 4x+4(x+80)=3800
4x+4x+320=3800
8x=3800-320
or 8x=3480
x=435
speed of one plane=435 m/h
speed of other plane=435+80=515 m/h
2.
Let he walks x hrs
then he take a taxi for 2-x hrs
4x+(2-x)50=31
4x+100-50x=31
-46x=-69

so he walks 3/2 hrs=1.5 hrs
travels by taxi=2-1.5=0.5 hrs
distance traveled by taxi=0.5×50=25 miles
Tony will get $8.26 back.
Here's why:
First, let's take $1.85 away from $13.59, because he has a coupon. That leaves us with $11.74
Second, do $20 - $11.74 to get your answer, $8.26