Two triangles are shown drawn inside a much larger triangle. These two triangles are similar (although not congruent). Thus, we can write and solve an equation of ratios along the way to finding the value of x.
Note that all three triangles shown are "3-4-5" triangles; this is because
3^2 + 4^2 = 5^2, or 9 + 16 + 25.
500 mi 400 mi
------------ = ------------ and so: 500x = 120000, or x= 240 (miles)
300 mi x
The distance x is 240 miles.
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