We turn -5,12 into polar coordinates. It's a Pythagorean Triple so
r = 13 Ф=arctan(-12/5) + 180° ( in the second quadrant )
so -5 = 13 cos Ф, 12 = 13 sin Ф
12 sin x - 5 cos x = 6.5
13 sinФ sin x + 13 cos Ф cos x = 6.5
13 cos(x - Ф) = 6.5
cos(x - Ф) = 1/2
cos(x - Ф) = cos 60°
x - Ф = ± 60° + 360° k integer k
x = Ф ± 60° + 360° k
x = 180° + arctan(-12/5) ± 60° + 360° k
That's the exact answer;
x ≈ 180° - 67.38° ± 60° + 360° k
x ≈ 122.62° ± 60° + 360° k
x ≈ { 62.62°, 182.62°} + 360° k, integer k
Answer:
b. Invalid, because the sample may not be representative of the population.
Step-by-step explanation:
A sample of around 10% of the population is needed to be representative.
In this question:
We have a population of 500,000, and a sample of 10,000.
10,000/500,000 = 1/50 = 0.02 = 2% of the population, so not representative, and option b is correct.
The correct answer maybe
Actually I don't understand ur question
Reflection across the x-axis followed by a reflection across the y-axis.
