Basic Geometry : Squares

Study concepts, example questions & explanations for Basic Geometry

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Example Questions

Example Question #461 : Quadrilaterals

Find the perimeter of a square given area is \(\displaystyle 49\).

Possible Answers:

\(\displaystyle 28\)

\(\displaystyle 24\)

\(\displaystyle 7\)

\(\displaystyle 49\)

Correct answer:

\(\displaystyle 28\)

Explanation:

To find perimeter, we must first find the side length and then multiply is by \(\displaystyle 4\).

\(\displaystyle A=s^2\Rightarrow s=\sqrt{A}=\sqrt{49}=7\)

\(\displaystyle P=4s=4\cdot7=28\)

Example Question #872 : Basic Geometry

Find the area of the square.

1

Possible Answers:

\(\displaystyle 900\)

\(\displaystyle 1200\)

\(\displaystyle 1600\)

\(\displaystyle 800\)

Correct answer:

\(\displaystyle 800\)

Explanation:

The diagonal of a square is also the hypotenuse of a right isosceles triangle that has the sides of the square as its legs.

Thus, we can use the Pythagorean Theorem to find the length of the sides of the square.

\(\displaystyle \text{Diagonal}^2=\text{side}^2+\text{side}^2\)

\(\displaystyle \text{Diagonal}^2=2(\text{side}^2)\)

\(\displaystyle \text{side}^2=\frac{\text{Diagonal}^2}{2}\)

Recall how to find the area of a square.

\(\displaystyle \text{Area}=\text{side}^2=\frac{\text{Diagonal}^2}{2}\)

Now, substitute in the value of the diagonal to find the area of the square.

\(\displaystyle \text{Area}=\frac{40^2}{2}\)

Solve.

\(\displaystyle \text{Area}=800\)

Example Question #35 : How To Find The Perimeter Of A Square

A square has an area of \(\displaystyle 49in^2\). Find the perimeter. 

Possible Answers:

\(\displaystyle 25in\)

\(\displaystyle 49in\)

\(\displaystyle 14in\)

\(\displaystyle 21in\)

\(\displaystyle 28in\)

Correct answer:

\(\displaystyle 28in\)

Explanation:

Since a square has four equal sides, finding the side lengths from the area is quite simple.

\(\displaystyle Area = Length(Width)\)

Since all the sides are equal in a square, the length and width are equal, meaning that \(\displaystyle Area = side ^2\). Plugging in the numbers gives us:

\(\displaystyle 49 = side^2\)

\(\displaystyle \sqrt{}49 = side\)

\(\displaystyle 7 = side\)

Now that we have found the length of each of the sides of the square, we simply add all the sides together, or multiply by 4 (because there are 4 sides in a square). 

\(\displaystyle 7(4) = 28in\)

Example Question #881 : Plane Geometry

Find the perimeter of a square inscribed in a circle that has a diameter of \(\displaystyle 2\sqrt2\).

Possible Answers:

\(\displaystyle 8\sqrt2\)

\(\displaystyle 8\)

\(\displaystyle 12\)

\(\displaystyle 16\)

Correct answer:

\(\displaystyle 8\)

Explanation:

1

Notice that the diameter of the circle is also the diagonal of the square. The diagonal of the square is also the hypotenuse of a right isosceles triangle that has the sides of the square as its legs.

\(\displaystyle \text{diameter}=\text{diagonal}\)

Now, use the Pythagorean theorem to find the length of the sides of the square.

\(\displaystyle \text{Diagonal}^2=\text{side}^2+\text{side}^2\)

\(\displaystyle 2(\text{side})^2=\text{Diagonal}^2\)

\(\displaystyle \text{side}^2=\frac{\text{Diagonal}^2}{2}\) 

\(\displaystyle \text{side}=\sqrt{\frac{\text{Diagonal}^2}{2}}=\frac{\text{Diagonal}\sqrt2}{2}\)

Now, substitute in the value of the diagonal to find the length of a side of the square.

\(\displaystyle \text{side}=\frac{2\sqrt2(\sqrt2)}{2}\)

Simplify.

\(\displaystyle \text{side}=2\)

Now, recall how to find the perimeter of a square:

\(\displaystyle \text{Perimeter}=4(\text{side})\)

Substitute in the value of the side to find the perimeter of the square.

\(\displaystyle \text{Perimeter}=4(2)\)

Solve.

\(\displaystyle \text{Perimeter}=8\)

Example Question #37 : How To Find The Perimeter Of A Square

Find the perimeter of a square inscribed in a circle that has a diameter of \(\displaystyle 3\sqrt2\).

Possible Answers:

\(\displaystyle 12\)

\(\displaystyle 12\sqrt2\)

\(\displaystyle 24\)

\(\displaystyle 16\)

Correct answer:

\(\displaystyle 12\)

Explanation:

1

Notice that the diameter of the circle is also the diagonal of the square. The diagonal of the square is also the hypotenuse of a right isosceles triangle that has the sides of the square as its legs.

\(\displaystyle \text{diameter}=\text{diagonal}\)

Now, use the Pythagorean theorem to find the length of the sides of the square.

\(\displaystyle \text{Diagonal}^2=\text{side}^2+\text{side}^2\)

\(\displaystyle 2(\text{side})^2=\text{Diagonal}^2\)

\(\displaystyle \text{side}^2=\frac{\text{Diagonal}^2}{2}\) 

\(\displaystyle \text{side}=\sqrt{\frac{\text{Diagonal}^2}{2}}=\frac{\text{Diagonal}\sqrt2}{2}\)

Now, substitute in the value of the diagonal to find the length of a side of the square.

\(\displaystyle \text{side}=\frac{3\sqrt2(\sqrt2)}{2}\)

Simplify.

\(\displaystyle \text{side}=3\)

Now, recall how to find the perimeter of a square:

\(\displaystyle \text{Perimeter}=4(\text{side})\)

Substitute in the value of the side to find the perimeter of the square.

\(\displaystyle \text{Perimeter}=4(3)\)

Solve.

\(\displaystyle \text{Perimeter}=12\)

Example Question #38 : How To Find The Perimeter Of A Square

Find the perimeter of a square inscribed in a circle that has a diameter of \(\displaystyle 4\sqrt2\).

Possible Answers:

\(\displaystyle 16\)

\(\displaystyle 12\)

\(\displaystyle 16\sqrt2\)

\(\displaystyle 24\)

Correct answer:

\(\displaystyle 16\)

Explanation:

1

Notice that the diameter of the circle is also the diagonal of the square. The diagonal of the square is also the hypotenuse of a right isosceles triangle that has the sides of the square as its legs.

\(\displaystyle \text{diameter}=\text{diagonal}\)

Now, use the Pythagorean theorem to find the length of the sides of the square.

\(\displaystyle \text{Diagonal}^2=\text{side}^2+\text{side}^2\)

\(\displaystyle 2(\text{side})^2=\text{Diagonal}^2\)

\(\displaystyle \text{side}^2=\frac{\text{Diagonal}^2}{2}\) 

\(\displaystyle \text{side}=\sqrt{\frac{\text{Diagonal}^2}{2}}=\frac{\text{Diagonal}\sqrt2}{2}\)

Now, substitute in the value of the diagonal to find the length of a side of the square.

\(\displaystyle \text{side}=\frac{4\sqrt2(\sqrt2)}{2}\)

Simplify.

\(\displaystyle \text{side}=4\)

Now, recall how to find the perimeter of a square:

\(\displaystyle \text{Perimeter}=4(\text{side})\)

Substitute in the value of the side to find the perimeter of the square.

\(\displaystyle \text{Perimeter}=4(4)\)

Solve.

\(\displaystyle \text{Perimeter}=16\)

Example Question #39 : How To Find The Perimeter Of A Square

Find the perimeter of a square inscribed in a circle that has a diameter of \(\displaystyle 5\sqrt2\).

Possible Answers:

\(\displaystyle 20\)

\(\displaystyle 20\sqrt2\)

\(\displaystyle 50\)

\(\displaystyle 25\sqrt2\)

Correct answer:

\(\displaystyle 20\)

Explanation:

1

Notice that the diameter of the circle is also the diagonal of the square. The diagonal of the square is also the hypotenuse of a right isosceles triangle that has the sides of the square as its legs.

\(\displaystyle \text{diameter}=\text{diagonal}\)

Now, use the Pythagorean theorem to find the length of the sides of the square.

\(\displaystyle \text{Diagonal}^2=\text{side}^2+\text{side}^2\)

\(\displaystyle 2(\text{side})^2=\text{Diagonal}^2\)

\(\displaystyle \text{side}^2=\frac{\text{Diagonal}^2}{2}\) 

\(\displaystyle \text{side}=\sqrt{\frac{\text{Diagonal}^2}{2}}=\frac{\text{Diagonal}\sqrt2}{2}\)

Now, substitute in the value of the diagonal to find the length of a side of the square.

\(\displaystyle \text{side}=\frac{5\sqrt2(\sqrt2)}{2}\)

Simplify.

\(\displaystyle \text{side}=5\)

Now, recall how to find the perimeter of a square:

\(\displaystyle \text{Perimeter}=4(\text{side})\)

Substitute in the value of the side to find the perimeter of the square.

\(\displaystyle \text{Perimeter}=4(5)\)

Solve.

\(\displaystyle \text{Perimeter}=20\)

Example Question #40 : How To Find The Perimeter Of A Square

Find the perimeter of a square inscribed in a circle that has a diameter of \(\displaystyle 7\sqrt2\).

Possible Answers:

\(\displaystyle 28\sqrt2\)

\(\displaystyle 98\)

\(\displaystyle 56\)

\(\displaystyle 28\)

Correct answer:

\(\displaystyle 28\)

Explanation:

1

Notice that the diameter of the circle is also the diagonal of the square. The diagonal of the square is also the hypotenuse of a right isosceles triangle that has the sides of the square as its legs.

\(\displaystyle \text{diameter}=\text{diagonal}\)

Now, use the Pythagorean theorem to find the length of the sides of the square.

\(\displaystyle \text{Diagonal}^2=\text{side}^2+\text{side}^2\)

\(\displaystyle 2(\text{side})^2=\text{Diagonal}^2\)

\(\displaystyle \text{side}^2=\frac{\text{Diagonal}^2}{2}\) 

\(\displaystyle \text{side}=\sqrt{\frac{\text{Diagonal}^2}{2}}=\frac{\text{Diagonal}\sqrt2}{2}\)

Now, substitute in the value of the diagonal to find the length of a side of the square.

\(\displaystyle \text{side}=\frac{7\sqrt2(\sqrt2)}{2}\)

Simplify.

\(\displaystyle \text{side}=7\)

Now, recall how to find the perimeter of a square:

\(\displaystyle \text{Perimeter}=4(\text{side})\)

Substitute in the value of the side to find the perimeter of the square.

\(\displaystyle \text{Perimeter}=4(7)\)

Solve.

\(\displaystyle \text{Perimeter}=28\)

Example Question #881 : Basic Geometry

Find the perimeter of a square inscribed in a circle that has a diameter of \(\displaystyle 9\sqrt2\).

Possible Answers:

\(\displaystyle 18\sqrt2\)

\(\displaystyle 72\)

\(\displaystyle 36\sqrt2\)

\(\displaystyle 36\)

Correct answer:

\(\displaystyle 36\)

Explanation:

1

Notice that the diameter of the circle is also the diagonal of the square. The diagonal of the square is also the hypotenuse of a right isosceles triangle that has the sides of the square as its legs.

\(\displaystyle \text{diameter}=\text{diagonal}\)

Now, use the Pythagorean theorem to find the length of the sides of the square.

\(\displaystyle \text{Diagonal}^2=\text{side}^2+\text{side}^2\)

\(\displaystyle 2(\text{side})^2=\text{Diagonal}^2\)

\(\displaystyle \text{side}^2=\frac{\text{Diagonal}^2}{2}\) 

\(\displaystyle \text{side}=\sqrt{\frac{\text{Diagonal}^2}{2}}=\frac{\text{Diagonal}\sqrt2}{2}\)

Now, substitute in the value of the diagonal to find the length of a side of the square.

\(\displaystyle \text{side}=\frac{9\sqrt2(\sqrt2)}{2}\)

Simplify.

\(\displaystyle \text{side}=9\)

Now, recall how to find the perimeter of a square:

\(\displaystyle \text{Perimeter}=4(\text{side})\)

Substitute in the value of the side to find the perimeter of the square.

\(\displaystyle \text{Perimeter}=4(9)\)

Solve.

\(\displaystyle \text{Perimeter}=36\)

Example Question #882 : Plane Geometry

Find the perimeter of a square inscribed in a circle that has a diameter of \(\displaystyle 11\sqrt2\).

Possible Answers:

\(\displaystyle 22\)

\(\displaystyle 44\)

\(\displaystyle 121\sqrt2\)

\(\displaystyle 22\sqrt2\)

Correct answer:

\(\displaystyle 44\)

Explanation:

1

Notice that the diameter of the circle is also the diagonal of the square. The diagonal of the square is also the hypotenuse of a right isosceles triangle that has the sides of the square as its legs.

\(\displaystyle \text{diameter}=\text{diagonal}\)

Now, use the Pythagorean theorem to find the length of the sides of the square.

\(\displaystyle \text{Diagonal}^2=\text{side}^2+\text{side}^2\)

\(\displaystyle 2(\text{side})^2=\text{Diagonal}^2\)

\(\displaystyle \text{side}^2=\frac{\text{Diagonal}^2}{2}\) 

\(\displaystyle \text{side}=\sqrt{\frac{\text{Diagonal}^2}{2}}=\frac{\text{Diagonal}\sqrt2}{2}\)

Now, substitute in the value of the diagonal to find the length of a side of the square.

\(\displaystyle \text{side}=\frac{11\sqrt2(\sqrt2)}{2}\)

Simplify.

\(\displaystyle \text{side}=11\)

Now, recall how to find the perimeter of a square:

\(\displaystyle \text{Perimeter}=4(\text{side})\)

Substitute in the value of the side to find the perimeter of the square.

\(\displaystyle \text{Perimeter}=4(11)\)

Solve.

\(\displaystyle \text{Perimeter}=44\)

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