Examples with solutions for Powers and Roots: The perimeter of a square

Exercise #1

A square has a side length of

(3125)232 (\sqrt{3}\cdot\sqrt{12}-5)^2\cdot3^2 .

Calculate its perimeter.

Video Solution

Step-by-Step Solution

To calculate the perimeter of a square, we need to first determine the length of one side and then use the formula for the perimeter of a square, which is given by 4×side length 4 \times \text{side length} .

The side length is given as (3125)232 (\sqrt{3}\cdot\sqrt{12}-5)^2\cdot3^2 . Let's simplify this expression step by step:

  • First, simplify the square roots: 3 \sqrt{3} and 12 \sqrt{12} .

    • 12=4×3=4×3=2×3 \sqrt{12} = \sqrt{4 \times 3} = \sqrt{4}\times \sqrt{3} = 2 \times \sqrt{3}
    • Thus, 3×12=3×2×3=2×3=6 \sqrt{3} \times \sqrt{12} = \sqrt{3} \times 2 \times \sqrt{3} = 2 \times 3 = 6 .
  • Next, substitute back into the expression: (65)232 (6 - 5)^2 \cdot 3^2 .
  • Simplify inside the parentheses: 65=1 6 - 5 = 1 , so we have 1232 1^2 \cdot 3^2 .
  • Calculate the squares: 12=1 1^2 = 1 and 32=9 3^2 = 9 .
  • Multiply the results: 1×9=9 1 \times 9 = 9 .

The side length of the square is therefore 9 9 .

Thus, the perimeter of the square is:

  • 4×9=36 4 \times 9 = 36 .

Therefore, the perimeter of the square is 36 36 .

Answer

36

Exercise #2

Given the area of the square ABCD is

3216 3^2\sqrt{16}

Find the perimeter.

Video Solution

Step-by-Step Solution

To find the perimeter of the square ABCD, we first need to determine the side length of the square using the given area. The area of a square is calculated using the formula: Area=s2 \text{Area} = s^2 , where s s is the side length of the square.

According to the problem, the area of the square is given by the expression 3216 3^2\sqrt{16} .

Let's simplify this expression:

  • First, calculate 32 3^2 , which is 9 9 .

  • Next, calculate 16 \sqrt{16} , which is 4 4 .

Now, multiply these results: 9×4=36 9 \times 4 = 36 .

Thus, the area of the square is 36 36 .

Since the area is s2=36 s^2 = 36 , we can solve for s s :

  • Find the square root of both sides: s=36 s = \sqrt{36} .

  • This gives s=6 s = 6 .

Now that we have the side length s=6 s = 6 , we can find the perimeter. The perimeter P P of a square is given by:

P=4s P = 4s .

Substituting the side length, we get:

  • P=4×6=24 P = 4 \times 6 = 24 .

The solution to the question is: 24 24

Answer

24 24

Exercise #3

Given a square whose area is

(3212)+23 (3^2-1^2)+2^3

What is the perimeter of this square?

Video Solution

Step-by-Step Solution

To solve this problem, we need to find the perimeter of a square given its area. The area of the square is given by the expression (3212)+23 (3^2-1^2)+2^3 .

Let us evaluate the expression to find the area:

  • Calculate 32 3^2 , which is 9 9 .
  • Calculate 12 1^2 , which is 1 1 .
  • Subtract to find 3212=91=8 3^2 - 1^2 = 9 - 1 = 8 .
  • Calculate 23 2^3 , which is 8 8 .
  • Add the results: 8+8=16 8 + 8 = 16 .

Therefore, the area of the square is 16 16 .

In general, the area of a square is given by the formula s2 s^2 , where s s is the side length of the square. To find the side length, we solve the equation:

  • s2=16 s^2 = 16 .
  • Taking the square root of both sides, we find s=16=4 s = \sqrt{16} = 4 .

The perimeter P P of a square with side length s s is given by the formula:

  • P=4s P = 4s .

Thus, substituting the value of s s :

  • P=4×4=16 P = 4 \times 4 = 16 .

Therefore, the perimeter of the square is 16 16 .

Answer

16 16

Exercise #4

ABCD is a square.

The length of the diagonal:
32×(3223)22 3\sqrt{2}\times\left(3^2-2^3\right)-2\sqrt{2}

AAABBBCCCDDDWhat is the perimeter of the square ABCD?

Video Solution

Step-by-Step Solution

The problem involves the square ABCD, and we need to determine its perimeter, given the expression for the length of its diagonal. Here's the step-by-step solution:

Let's denote the side of the square ABCD as s s . The diagonal of a square can be calculated using Pythagoras' theorem as:

  • d=s2 d = s\sqrt{2}

The problem provides an expression for the length of the diagonal:

  • 32×(3223)22 3\sqrt{2}\times(3^2-2^3)-2\sqrt{2}

Let's simplify this expression step by step.

First, calculate the powers:

  • 32=9 3^2 = 9

  • 23=8 2^3 = 8

Subtract these values:

  • 3223=98=1 3^2 - 2^3 = 9 - 8 = 1

Substitute back into the expression for the diagonal:

  • 32×122 3\sqrt{2} \times 1 - 2\sqrt{2}

This simplifies to:

  • 3222 3\sqrt{2} - 2\sqrt{2}

  • (32)2=12=2 (3 - 2)\sqrt{2} = 1\sqrt{2} = \sqrt{2}

So, the length of the diagonal is 2 \sqrt{2} .

We know from the formula for the diagonal of a square that d=s2 d = s\sqrt{2} . Given d=2 d = \sqrt{2} , we can equate:

  • s2=2 s\sqrt{2} = \sqrt{2}

Thus:

  • s=1 s = 1

Therefore, the perimeter of the square ABCD is:

  • 4×s=4×1=4 4 \times s = 4 \times 1 = 4

Hence, the perimeter of the square ABCD is 4.

Answer

4