Given:ABCD is a rhombus.
To prove:DE congruent to BE.
In rombus, we know opposite angle are equal.
so, angle DCB = angle BAD
SINCE, ANGLE DCB= BAD
SO, In triangle DCA
angle DCA=angle DAC
similarly, In triangle ABC
angle BAC=angle BCA
since angle BCD=angle BAD
Therefore, angle DAC =angle CAB
so, opposite sides of equal angle are always equal.
so,sides DC=BC
Now, In triangle DEC and in triangle BEC
1. .DC=BC (from above)............(S)
2ANGLE CED=ANGLE CEB (DC=BC)....(A)
3.CE=CE (common sides)(S)
Therefore,DE is congruent to BE (from S.A.S axiom)
So the formula to workout the area of a rectangle is height X width
so 11/3 x 5/8
which is 55/24 ft if they want a mixed number then... 2 
hope this helps
Just a guess, but the angle inside the triangle that's not x or y is the remaining angle after subtracting the 30 degrees shown. That makes the non labeled angle inside the triangle 150 degrees. since all triangles are 180 degrees, this means x and y add up to 30. They look roughly the same, so i'd guess they're both 15 degrees.
The unit rate would be 3 trucks per 1 hour you can find this by dividing 18 and 6 by 6
