Given ABC congruent triangle def, ab = 5, s triangle ABC = 10, find the height of de side in triangle def

Given ABC congruent triangle def, ab = 5, s triangle ABC = 10, find the height of de side in triangle def

Triangle ABC congruent triangle def
Then it corresponds to the edge and the area
And ab = 5, s triangle ABC = 10,
Then de = 5, s triangle def = 10,
The height of de side in triangle def = 4