Triangle XYZ ~ triangle JKL. Use the image to answer the question.

a triangle XYZ with side XY labeled 8.7, side XZ labeled 8.2, and side YZ labeled 7.8 and a second triangle JKL with side JK labeled 12.18

Determine the measurement of KL.

KL = 9.29
KL = 10.92
KL = 10.78
KL = 11.48

1 answer

Since triangles XYZ and JKL are similar (denoted by the symbol "~"), the ratios of their corresponding sides are equal.

Given the measurements:

  • For triangle XYZ:

    • Side XY = 8.7
    • Side XZ = 8.2
    • Side YZ = 7.8
  • For triangle JKL:

    • Side JK = 12.18
    • Side KL = ?

To find the length of KL, we can set up a ratio between the sides of the two triangles:

\[ \frac{XY}{JK} = \frac{YZ}{KL} \]

From the information given, we can use side XY and JK:

\[ \frac{8.7}{12.18} = \frac{7.8}{KL} \]

Now, we will cross-multiply to solve for KL:

\[ 8.7 \cdot KL = 7.8 \cdot 12.18 \]

Calculating the right side:

\[ 7.8 \cdot 12.18 = 95.376 \]

Now we have:

\[ 8.7 \cdot KL = 95.376 \]

Next, we divide both sides by 8.7 to isolate KL:

\[ KL = \frac{95.376}{8.7} \]

Calculating KL:

\[ KL \approx 10.95 \]

This value is closest to 10.92, so the measurement of KL is:

KL = 10.92