=
Is it?
+
De?
. BD？
=
AB？
=
(AB-AE)？
+
De?
=
AB？
-
2AB*AE
+
AE？
+
De?
. therefore
2AE*AB
=
AE？
+
De? . Also because
Triangle AED is a right triangle, so
AD？
=
AE？
+
De? . therefore
AD？
=
2AE*AB
. Question 2: Find the area of triangle ACD: Because
(CD+AE)？
+
De?
=
AC？
, namely
(CD+(AB-CD)/2)？
+
CD？
=
AB？
, namely
3AB？
-2AB*CD
-5CD？
=
0, that is
(3AB
-
5CD)*(AB
+
CD)=0，CD
Not equal to negative number
therefore
laser record
=
3AB/5. Because
Height of triangle ABC
=
De,
Height of triangle ACD
=
De. Therefore
ABC area
=
AB*
DE/2
=
50,
Regional ACD
=
DC * Germany /2
=
3AB/5*DE/2
=
3/5
*
Area ABC=
3/5
*
50
=
30。 therefore
The area of triangle ACD is
30。