Answer:
the answer is A≈9160.88
Step-by-step explanation:
- A=4πr2=4·π·272≈9160.88418
- where as a = area
X² - 6x + 7 = 0
x² - 6x = -7
x² - 6x + 9 = -7 + 9
(x-3)² = 2
To solve this problem you must apply the proccedure shown below:
1. You have that:
- T<span>he equation d=1/2(n(n-3)) gives the number of diagonals for the polygon.
- The polygon that has 65 diagonals..
2. When you clear n, you obtain:
d=n(n-3)/2
d=(n^2-3n)/2
2x65=n^2-3n
n^2-3n-130=0
3. When you solve the quadratic equation, you obtain:
n=13
Therefore, the answer is: 13 sides. </span>
9514 1404 393
Answer:
20 miles
Step-by-step explanation:
The north and east distances form the legs of a right triangle. The straight-line distance between the trains is the hypotenuse of that triangle. The Pythagorean theorem can be used to find the length of the hypotenuse (d).
d² = 12² +16²
d² = 144 +256 = 400
d = √400 = 20
The two trains are 20 miles apart.
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<em>Additional comment</em>
You may recognize the given distances are in the ratio 3 : 4. You may recall that side ratios of 3 : 4 : 5 make a right triangle. If so, you recognize that the straight-line distance is (4 miles)×5 = 20 miles. (3:4:5 right triangles show up often in algebra and geometry problems, so might be something you want to look for.)
