Step-by-step explanation:
In ∆'s ABC and CDE
AngleCAB = Angle CED = 90°
Angle ACB = Angle DCE. (vertically opposite angle)
Angle CDE = Angle CBA. (Alternate Interior Angle)
By AAA congruency
∆ ABC congruent ∆ CDE
By CPCT,
AC = EC
4x - 3 = 2x + 6
2x = 9
x = 9/2
AE = 15 + 15
= 30 ft
