In square ABCD, e and F are on BC and CD, respectively, ∠ EAF = 45 °, try to explain s △ AEF = s △ Abe + s △ ADF

In square ABCD, e and F are on BC and CD, respectively, ∠ EAF = 45 °, try to explain s △ AEF = s △ Abe + s △ ADF

Extending FD to h, making HD = be, connecting ah, it is easy to prove that ah = AE, the area of triangle ahd is equal to the area of triangle Abe, because the angle EAF = 45 degrees, it is easy to prove that the angle HAF = 45 degrees, so triangle AEF and triangle AHF are congruent, that is, the area is also equal,