Answer:
10 cm
Step-by-step explanation:
The diagonal d divides the rectangle into 2 right triangles with legs 8 and 6 and hypotenuse d
Using Pythagoras' identity in one of the right triangles, then
d² = 8² + 6² = 64 + 36 = 100 ( take square root of both sides )
d = 
= 10 cm
I'm a bit confused however this is what I have come up with. I did not use the values for AB or DE at all. As a warning, my geometry skills are not great as I do not remember much from 8th grade.
If my memory serves me right, angle BCD's degree must equal's angle DAB's degree, so 110. A parallelogram's angle sums up to 360. If you add BCD and DAB's measurements, it equals 220, subtract this number from 360 and you get 140. angles ABC and ADC must also equal one another so if we divide 140 we get the individual angle degrees. If you do this you should get 70 degrees.
The complete question in the attached figure
we know that
perimeter=24 ft
[the perimeter of a rectangle]=2*8+2*x-----------> 16+2x
24=16+2x-------> 2x=24-16----------> 2x=8----------> x=4 ft
the answer is
the option C) x=4 ft
The answer to that question is x=20
