trigonometry
I am attempting to find the angle between the 2 points (50.573,-210.265) and (117.833,-80.550).
Is my calculation correct because a program is giving me a different answer? It says the angle is 27'24'27.27 DMS
dx = x2 - x1;
dy = y2 - y1;
angle = Atan2(dy,dx) * 180 / PI;
angle = 62.59242
My result is 62.59242 degrees but the program says its 27'24'27.27 DMS. Which is correct?
Also if the points were 3d would that affect the angle? Or does the z axis not impact on the horizontal angle?
Yes, two-argument arctangent is intended precisely for your situation. You didn't specify what specific language you have, so: check the docs to see whether it takes the vertical coordinate y first (atan2(y,x)) or the horizontal coordinate x first (atan2(x,y)). One thing is generally agreed upon for two-argument arctangent: the angles (in radians) returned are within the interval (−π,π]
atan2() is also designed to handle the case where one of the coordinates is zero. I haven't checked how atan2(0,0) evaluates in Java, but it's indeterminate (NaN) in some systems and zero in other systems. If you need results in degrees, just perform the usual conversions
Cite: J.M
BF is the ground level.
Write EG in terms of angle $50^\circ$.Find $x$. Then the height will be $x\tan 46^\circ + 10$
Best Answer
I agree with your calculation. It appears they are defining it with the arguments switched. The fact that you answer is $90-$theirs supports this. Note that there is no angle between two points. What you have is the angle between the line through those points and the $x$ axis.