The diameter of a circle is 4cm. Which equation can be used to find its circumference? A. C=pi x2 B. C=pi x 4 C. C=pi x 4/2 D. C
1 answer:
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Answer:
The two airplanes are about 330miles apart.
Step-by-step explanation:
The diagram interpreting the question has been attached to this response.
As shown in the diagram,
i. the airplanes leave at point C.
ii. at 2.00pm the first and second airplanes are at points A and B respectively, where they are 312miles and 487miles away from the starting point C in directions due north and N42E from the point C.
iii. the points A, B and C form a triangle with sides a, b and c.
To solve for the value of c which is the distance between the two planes at 2.00pm, the cosine rule is used.
c² = a² + b² - 2abcosC --------------(i)
where;
b = 312miles
a = 487miles
C = 42°
Substitute these values into equation (i) and solve as follows;
c² = (487)² + (312)² - 2(312)(487)cos(42)
c² = (237169) + (97344) - 303888cos(42)
c² = (237169) + (97344) - 303888(0.7431)
c² = 334513 - 225819.1728
c² = 108693.8272
<em>Take the square root of both sides</em>
√c² = √108693.8272
c = 329.69
c ≅ 330miles
Therefore, the two airplanes are far apart by 330miles
