Answer:
<em>Area of polygon D = 10 square units</em>
Step-by-step explanation:
<u>Given:</u>
Polygon <em>C </em>has an area of 40 square units.
It is scaled with a scale factor of
to form a new polygon D.
<u></u>
<u>To find:</u>
The area of polygon D = ?
<u>Solution:</u>
When any polygon is scaled to half, then all the sides of new polygon are half of the original polygon.
And the area becomes one-fourth of the original polygon.
Let us consider this by taking examples:
- First of all, let us consider a right angled triangle with sides <em>6, 8 and 10 units.</em>
Area of a right angled triangle is given by:
![A = \dfrac{1}{2} \times Base \times Height\\\Rightarrow A = \dfrac{1}{2} \times 6 \times 8 = 24\ sq\ units](https://tex.z-dn.net/?f=A%20%3D%20%5Cdfrac%7B1%7D%7B2%7D%20%5Ctimes%20Base%20%5Ctimes%20Height%5C%5C%5CRightarrow%20A%20%3D%20%5Cdfrac%7B1%7D%7B2%7D%20%5Ctimes%206%20%5Ctimes%208%20%3D%2024%5C%20sq%5C%20units)
If scaled with a factor
, the sides will be 3, 4 and 5.
New area, A':
![A' =\dfrac{1}{2} \times 3 \times 4 = 6\ sq\ units = \dfrac{1}4\times A](https://tex.z-dn.net/?f=A%27%20%3D%5Cdfrac%7B1%7D%7B2%7D%20%5Ctimes%203%20%5Ctimes%204%20%3D%206%5C%20sq%5C%20units%20%3D%20%5Cdfrac%7B1%7D4%5Ctimes%20A)
i.e. Area becomes one fourth.
- Let us consider a rectangle now.
Sides be 8 and 10 units.
Area of a rectangle, A =
= 8
10 = 80 sq units.
Now after scaling, the sides will be 4 and 5 units.
New Area, A' = 4
5 =20 sq units
So, ![\bold{A' = \frac{1}4 \times A}](https://tex.z-dn.net/?f=%5Cbold%7BA%27%20%3D%20%5Cfrac%7B1%7D4%20%5Ctimes%20A%7D)
Now, we can apply the same in the given question.
Area of polygon D = ![\bold{\frac{1}{4}}](https://tex.z-dn.net/?f=%5Cbold%7B%5Cfrac%7B1%7D%7B4%7D%7D)
Area of polygon C
Area of polygon D = ![\bold{\frac{1}{4}}](https://tex.z-dn.net/?f=%5Cbold%7B%5Cfrac%7B1%7D%7B4%7D%7D)
40 = <em>10 sq units</em>