Louisville is 14 mi due north of farmville, stanton is due east of farmville, and louisville is 25 mi from stanton.
how far apart are farmville and stanton? round to the nearest tenth of a mile.

You can draw a right triangle with one side being the known distance from Farmville to Louisville, 14 mi.

The other side, call it x, is the requested distance from Farmville to Stanton.

The hypotenuse is the 25 mi that separate Farmville and Stanton.

Use Pythagora's theorem:

25^2 = x^2 + 14^2

x^2 = 25^2 - 14 ^2 = 625 - 196 = 429

Take square root from both sides

x = √429 = 20,7 mi.