A rectangle is inscribed in a circle such that each vertex of the rectangle lies on the circumference of the circle. The diagonal of the rectangle is twice the length of the shortest side of the rectangle. The area of the rectangle is [tex]\(1,089 \sqrt{3}\)[/tex] square units. What is the length, in units, of the diameter of the circle?



Answer :

To find the length of the diameter of the circle in which a rectangle is inscribed, given that the area of the rectangle is 1,089√3 square units, and the rectangle's diagonal is twice the length of its shortest side, we will proceed step-by-step.

1. Identify Variables and Relationships:
- Let the length of the shortest side of the rectangle be [tex]\(a\)[/tex].
- Let the length of the other side be [tex]\(b\)[/tex].
- Given that the diagonal is twice the length of the shortest side, the diagonal is [tex]\(2a\)[/tex].

2. Area of the Rectangle:
- The area of the rectangle is given as [tex]\(1089\sqrt{3}\)[/tex] square units.
- Therefore, we have the relationship: [tex]\(a \cdot b = 1089\sqrt{3}\)[/tex].

3. Using the Pythagorean Theorem:
- The rectangle's diagonal forms a right triangle with its sides [tex]\(a\)[/tex] and [tex]\(b\)[/tex].
- According to the Pythagorean theorem, the relationship between the sides and the diagonal of a rectangle is: [tex]\(a^2 + b^2 = (2a)^2\)[/tex].
- Simplifying this gives: [tex]\(a^2 + b^2 = 4a^2\)[/tex].
- Further simplification yields: [tex]\(b^2 = 3a^2\)[/tex].

4. Substitute and Simplify:
- We know [tex]\(b = \sqrt{3}a\)[/tex] from the equation [tex]\(b^2 = 3a^2\)[/tex].
- Substitute [tex]\(b\)[/tex] back into the area equation:
[tex]\[ a \cdot (\sqrt{3}a) = 1089\sqrt{3} \][/tex]
- This simplifies to:
[tex]\[ a^2\sqrt{3} = 1089\sqrt{3} \][/tex]
- By dividing both sides by [tex]\(\sqrt{3}\)[/tex], we get:
[tex]\[ a^2 = 1089 \][/tex]
- Solving for [tex]\(a\)[/tex]:
[tex]\[ a = \sqrt{1089} = 33 \][/tex]

5. Determine the Length of the Other Side ([tex]\(b\)[/tex]):
- From the relationship [tex]\(b = \sqrt{3}a\)[/tex]:
[tex]\[ b = \sqrt{3} \cdot 33 \approx 57.16 \][/tex]

6. Calculate the Diameter of the Circle:
- The diameter of the circle is the same as the diagonal of the rectangle.
- Since the diagonal is [tex]\(2a\)[/tex]:
[tex]\[ \text{Diameter} = 2 \cdot 33 = 66 \][/tex]

Thus, the length of the diameter of the circle is 66 units.