ABCD is a square. Triangle DEF is equilateral. Triangle ADE is isosceles with AD = AE. CDF is a straight line. Showing all your steps, calculate the size of angle AEF

Answer:
90°
Step-by-step explanation:
the sum of all angles in a triangle is always 180°.
in an equilateral triangle also all 3 angles are equal and therefore 180/3 = 60°.
angle EDF = 60°.
angle DEF = 60°
all angles in a square are 90°.
so, angle ADC = 90°.
and therefore, ADF = 90°.
the angle ADE is then 90-60 = 30°.
the triangle ADE is isoceles (both legs are equal, and both angles of the legs with the baseline are equal).
so, the angle AED = angle ADE = 30°
the angle AEF is then angles AED + DEF = 30 + 60 = 90°