I think you have to follow someone and ask them to be your tutor.
The area of a circle in terms of the circle's radius
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is

Differentiating both sides with respect to
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, you get
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
Answer:
the answer is A please give me hearts and stars because it is correct.
Step-by-step explanation:
it is easy you just mark out the ones you know that is wrong and you are left with the answer a which is very correct.
Answer:
SLOPE: 1
Y-Intercept: (0,4)
Step-by-step explanation: