Consider the parallelogram shown below.
The lengths of the sides are a and b.
The lengths of the diagonals are 2x and 2y.
Because the diagonals are both congruent and perpendicular, therefore there are two right triangles as shown.
Note that x = y.
Because x = y, each right triangle is isosceles and has the angles 90°, 45° and 45°.
From the Pythagorean theorem,
For one right triangle,
a² = x² + y² = x² + x² = 2x².
For the other right triangle,
b² = y² + x² = x² + x² = 2x²
Therefore
a² = b²
a = b
It follows that all sides of the parallelogram are equal and each angle is
45+45 = 90°
Therefore the parallelogram is a square.
QUESTION :-
what is the value of x to the nearest whole number?
ANSWER :-

SO
the nearest whole number-->
20.7 --> approximately --> 21 units
Answer:
On average, the land moved 0,14 cm each year.
Step-by-step explanation:
To know how much did, on average, the land move, we should divide the total number of cm over the total number of years:
x=24.8 cm/175 years
x=0,1417 cm each year
If we divide years over cm we will get x in years each cm, which is wrong.
Because the problem asks for the answer rounded to the hundredths place:
x= 0,14 cm each year
Answer:
x = 8
Step-by-step explanation:
The explanation are the pictures. I hope I gave you the correct answer.