Consider expression
First, you can factor it:

Since x is integer number, then you can see that x-1 is previous integer number (x-1 is 1 unit smaller than x).
Therefore, x-1 and x are two consecutive integers. When you have two consecutive integers, one of them is always even and one is always odd. Multiplying even integer number by odd integer number you always get even integer number.
Thus,
is always even.
Could you show a picture so i could understand a little bit better?
For this case we have to define trigonometric relations of rectangular triangles that:
- The cosine of an angle is given by the leg adjacent to the angle on the hypotenuse of the triangle.
- The sine of an angle is given by the leg opposite the angle on the hypotenuse of the triangle.
Then, according to the figure we have:

Answer:

Option D
Step-by-step explanation:
<h2><u>☼︎</u><u>Given :</u></h2>
- The floor of a drawing room consist of 2000 tiles .Each tiles is rectangular in shape , of dimensions ,30 cm × 20 cm.

<h2><u>☼︎</u><u>To Find :</u></h2>

<h2><u>☼︎</u><u>Solution :</u></h2>
<u>~ Formula </u><u>U</u><u>s</u><u>e</u><u>d</u><u>:</u>

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
<u>~ Calculating the</u><u> Area of Tiles </u>




<u>~ Calculating Area of the </u><u>Drawing Room :</u>




<u>~ Therefore :</u>
❝ Area of the Drawing room is 1200000 cm² or 12000 m² . ❞
