Question 343460
Let the starting point be the origin (0,0).
Let east be positive x, west negative x.
Let north be positive y, south negative y.
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Starting at (0,0)
120km south: (0,0)+(0,-120)=(0,-120)
150 km east:(0,-120)+(150,0)=(150,-120)
200 km north: (150,-120)+(0,200)=(150,80)
The aircraft's currently 150 east and 80 miles north of the starting point.
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Use the distance formula to find the distance.
{{{D^2=(x2-x1)^2+(y2-y1)^2}}}
{{{D^2=(150-0)^2+(80-0)^2}}}
{{{D^2=22500+6400}}}
{{{D^2=28900}}}
{{{highlight(D=170)}}}km