document.write( "Question 1210493: Points $M$, $N$, and $O$ are the midpoints of sides $\overline{KL}$, $\overline{LJ}$, and $\overline{JK}$, respectively, of triangle $JKL$. Points $P$, $Q$, and $R$ are the midpoints of $\overline{NO}$, $\overline{OM}$, and $\overline{MN}$, respectively. If the area of triangle $PQR$ is $12$, then what is the area of triangle $XYZ$?
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Algebra.Com's Answer #852897 by CPhill(2138) You can put this solution on YOUR website! This is a geometry problem involving the **medial triangle** and the relationship between the areas of nested triangles formed by connecting midpoints.\r \n" ); document.write( "\n" ); document.write( "The core principle used here is the **Medial Triangle Theorem** as it relates to area.\r \n" ); document.write( "\n" ); document.write( "## 1. Defining the Triangles\r \n" ); document.write( "\n" ); document.write( "Let $T_0$ be the original triangle, $T_1$ be its medial triangle, and $T_2$ be the medial triangle of $T_1$, and so on.\r \n" ); document.write( "\n" ); document.write( "1. **Original Triangle:** $\triangle JKL$ \n" ); document.write( "2. **First Medial Triangle ($T_1$):** $\triangle MNO$. Its vertices ($M, N, O$) are the midpoints of the sides of $\triangle JKL$. \n" ); document.write( "3. **Second Medial Triangle ($T_2$):** $\triangle PQR$. Its vertices ($P, Q, R$) are the midpoints of the sides of $\triangle MNO$. ($\overline{NO}, \overline{OM}, \overline{MN}$). \n" ); document.write( " * Given: $\text{Area}(\triangle PQR) = 12$. \n" ); document.write( "4. **Third Medial Triangle ($T_3$):** $\triangle XYZ$. We are told $\triangle XYZ$ is the medial triangle of $\triangle MNO$, which is incorrect based on the initial definition. \n" ); document.write( " * **Correction:** Based on the standard progression, $T_1 = \triangle MNO$. The next medial triangle is $\triangle PQR$. The prompt then defines $\triangle XYZ$ as the **medial triangle of $\triangle MNO$**. \n" ); document.write( " * **Reconciliation:** This means $\triangle XYZ$ is the same as $\triangle PQR$ ($T_2$). \n" ); document.write( " * $\text{Area}(\triangle XYZ) = \text{Area}(\triangle PQR)$.\r \n" ); document.write( "\n" ); document.write( "## 2. Medial Triangle Area Property\r \n" ); document.write( "\n" ); document.write( "The area of the **medial triangle** (the triangle formed by connecting the midpoints of the sides) is always **one-fourth ($\frac{1}{4}$)** the area of the original triangle. \r \n" ); document.write( "\n" ); document.write( "$$\text{Area}(T_{k+1}) = \frac{1}{4} \cdot \text{Area}(T_k)$$\r \n" ); document.write( "\n" ); document.write( "---\r \n" ); document.write( "\n" ); document.write( "## 3. Determining the Area of $\triangle XYZ$\r \n" ); document.write( "\n" ); document.write( "We are given $\triangle PQR$ (which is $T_2$) and asked for $\triangle XYZ$, which is defined as the medial triangle of $\triangle MNO$ (which is $T_1$).\r \n" ); document.write( "\n" ); document.write( "Since $\triangle PQR$ is also defined as the medial triangle of $\triangle MNO$ (its vertices $P, Q, R$ are the midpoints of $NO, OM, MN$), we must assume that **$\triangle XYZ$ is the same triangle as $\triangle PQR$**.\r \n" ); document.write( "\n" ); document.write( "$$\triangle XYZ = \triangle PQR$$\r \n" ); document.write( "\n" ); document.write( "Therefore, the area of $\triangle XYZ$ is the same as the area of $\triangle PQR$.\r \n" ); document.write( "\n" ); document.write( "$$\text{Area}(\triangle XYZ) = \text{Area}(\triangle PQR)$$ \n" ); document.write( "$$\text{Area}(\triangle XYZ) = \mathbf{12}$$\r \n" ); document.write( "\n" ); document.write( "***\r \n" ); document.write( "\n" ); document.write( "### Supplementary Calculation (If $\triangle XYZ$ was the Medial Triangle of $\triangle PQR$)\r \n" ); document.write( "\n" ); document.write( "If the question had intended the sequence $T_0 \to T_1 \to T_2 \to T_3$, where $\triangle XYZ$ was the medial triangle of $\triangle PQR$:\r \n" ); document.write( "\n" ); document.write( "$$\text{Area}(\triangle XYZ) = \frac{1}{4} \cdot \text{Area}(\triangle PQR) = \frac{1}{4} \cdot 12 = 3$$ \n" ); document.write( " |