The height CF is drawn in the isosceles triangle CDE with the base CE. Find the ECF angle if the angle is D = 54 degrees.

Since the triangle ABC is isosceles, its angles to the base of the CE are equal. Angle DCE = DEC = (180 – 54) / 2 = 63.

The CFE triangle is rectangular since CF is the height of the CDE triangle, then the angle ECF = 180 – 90 – 63 = 27.

Answer: The ECF is 27.

One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.