Parallelogram Perimeter: Express in Terms of X When One Side is Double Another

Question

Given a parallelogram in which the length of one side is greater than 2 of the length of another side and given that the length of the longest side is X:

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Express by X the perimeter of the parallelogram.

Video Solution

Solution Steps

00:12 First, express the perimeter of the parallelogram using X.
00:16 Remember, in a parallelogram, opposite sides are equal.
00:29 Notice the longer sides of the parallelogram.
00:39 Let's look at the ratio of the sides based on the given information.
00:46 Let's call side A B as X.
00:50 Next, use X to find the length of side A C.
00:59 Again, opposite sides in a parallelogram are equal, so remember this.
01:04 To find the perimeter, add up all the sides of the parallelogram.
01:16 Now, substitute the values you have and solve to find the perimeter.
01:28 Great job! And that's how we solve this problem.

Step-by-Step Solution

To solve this problem, we need to calculate the perimeter of the parallelogram using given information. Here are the steps to find the solution:

  • Step 1: Identify the Longest Side.
    The longest side of the parallelogram, denoted by X X , is given as a a . Therefore, a=X a = X .
  • Step 2: Determine the Other Side Length.
    Given a>2b a > 2b , typically X=2b X = 2b as a common interpretation for solving problems.
    Thus, the other side b b is half the longer side: b=X2 b = \frac{X}{2} .
  • Step 3: Apply the Perimeter Formula.
    The perimeter P P of a parallelogram is calculated as P=2(a+b) P = 2(a + b) .
    Plug in the values: a=X a = X , b=X2 b = \frac{X}{2} .
    Thus, perimeter P=2(X+X2)=2(2X2+X2)=2(3X2)=3X P = 2\left(X + \frac{X}{2}\right) = 2\left(\frac{2X}{2} + \frac{X}{2}\right) = 2\left(\frac{3X}{2}\right) = 3X .

Therefore, the perimeter of the parallelogram in terms of X X is 3X \mathbf{3X} .

Answer

3X