Find X in Geometric Figure: Area 21 with Side Length 3

To solve this problem, we'll use the area formula for a parallelogram:

• Step 1: Identify and assign base and height. Assume $X$ is the base and the given side (3) is the height.
• Step 2: Apply the formula $S = b \times h$, where $b$ is base and $h$ is height.
• Step 3: Since $S = 21$, substitute it into the equation $21 = X \times 3$.
• Step 4: Solve for $X$.

Let's work through these steps:

Step 1: Assume $X$ is the base, and 3 is the height.

Step 2: Use the formula $S = b \times h = X \times 3$.

Step 3: Substitute $S = 21$:

$21 = X \times 3$

Step 4: Solve for $X$:

$X = \frac{21}{3}$

Simplifying gives:

$X = 7$

Therefore, the solution to the problem is $X = 7$.