Triangle DEF is equilateral. Find AE.
DA = 3, AF = 2
Law of Cosines
AE^2 = AF^2 + FE^2 - 2 (AF * FE) cos (60°)
AE^2 = 2^2 + 5^2 - 2(2* 5) (1/2)
AE^2 = 19
AE = sqrt (19)
