Answer is 18 and value of x is 0
Area = PI * radius^2
Circumference = 2 * PI * radius
radius = Circumference / 2 * PI
So, Area = PI * (Circumference / 2 *PI) * (Circumference / 2 *PI)
So, Area = Circumference^2 / (4*PI)
Answer:
8/11
Step-by-step explanation:
2 2/3 = 8/3
8/3 x 3/11 = 24/33
24/33 = 8/11
Answer:
x = 10
Step-by-step explanation:
You can try the answers to see which works. (The first one does.)
Or, you can solve for the variable:
Divide by 75
... (1/5)^(x/5) = 3/75 = 1/25
Recognize that 25 = 5^2, so ...
... (1/5)^(x/5) = (1/5)^2
Equating exponents, you have
... x/5 = 2
... x = 10 . . . . . multiply by 5
_____
You can also start by taking logarithms:
... log(75) +(x/5)log(1/5) = log(3)
... (x/5)log(1/5) = log(3) -log(75) = log(3/75) = log(1/25) . . . . simplify the log
... x/5 = log(1/25)/log(1/5) = 2 . . . . . simplify (or evaluate) the log expression
... x = 10 . . . . . multiply by 5
_____
"Equating exponents" is essentially the same as taking logarithms.
t - time, d - distance, v - speed
![d=39 \ mi \\ v=26 \ \frac{mi}{h} \\ \\ t=\frac{39}{26}=\frac{3 \times 13}{2 \times 13}=\frac{3}{2}=1.5 \ [h]](https://tex.z-dn.net/?f=d%3D39%20%5C%20mi%20%5C%5C%0Av%3D26%20%5C%20%5Cfrac%7Bmi%7D%7Bh%7D%20%5C%5C%20%5C%5C%0At%3D%5Cfrac%7B39%7D%7B26%7D%3D%5Cfrac%7B3%20%5Ctimes%2013%7D%7B2%20%5Ctimes%2013%7D%3D%5Cfrac%7B3%7D%7B2%7D%3D1.5%20%5C%20%5Bh%5D)
It will take
1.5 h.
