Math Problem Statement

Both figures shown below are trapezoids. ABCD ~ WXYZ. What is the value of p?

Solution

We are given two trapezoids, ABCDABCD and WXYZWXYZ, which are similar (denoted ABCDWXYZABCD \sim WXYZ). Our task is to find the value of pp, which represents the length of side CDCD in trapezoid ABCDABCD.

Similarity of Trapezoids:

Since the trapezoids are similar, the corresponding sides are proportional. This gives us the relationship:

ABWX=BCXY=CDYZ=DAZW\frac{AB}{WX} = \frac{BC}{XY} = \frac{CD}{YZ} = \frac{DA}{ZW}

Given Measurements:

From the image:

  • In trapezoid WXYZWXYZ:

    • WX=7mmWX = 7 \, \text{mm}
    • XY=13mmXY = 13 \, \text{mm}
    • YZ=10mmYZ = 10 \, \text{mm}
    • ZW=13mmZW = 13 \, \text{mm}
  • In trapezoid ABCDABCD:

    • AB=13.3mmAB = 13.3 \, \text{mm}
    • BC=24.7mmBC = 24.7 \, \text{mm}
    • DA=24.7mmDA = 24.7 \, \text{mm}
    • CD=pmmCD = p \, \text{mm} (unknown)

Find the Scaling Ratio:

We can find the scale factor using corresponding sides. Let's use the ratio of ABAB to WXWX:

ABWX=13.371.9\frac{AB}{WX} = \frac{13.3}{7} \approx 1.9

This means every side in trapezoid ABCDABCD is approximately 1.9 times longer than the corresponding side in trapezoid WXYZWXYZ.

Solve for pp:

Using the ratio for the sides CDCD and YZYZ:

CDYZ=ABWX=1.9\frac{CD}{YZ} = \frac{AB}{WX} = 1.9

So:

p=1.9×YZ=1.9×10=19mmp = 1.9 \times YZ = 1.9 \times 10 = 19 \, \text{mm}

Thus, the value of pp is 19mm19 \, \text{mm}.

Would you like a further breakdown or have any questions?

Related Questions:

  1. What other properties of similar figures can help in solving problems like this?
  2. How does the ratio of areas relate to the ratio of corresponding sides in similar figures?
  3. Can you solve for other unknowns if trapezoids were not similar?
  4. What happens to the ratio if the figures are scaled differently along different axes?
  5. How can trapezoid properties (like the height) be used in solving for area?

Tip:

Always check the scale factor using multiple pairs of corresponding sides to ensure accuracy when working with similar figures.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Geometry
Similarity of Shapes
Proportional Relationships

Formulas

\(\frac{AB}{WX} = \frac{BC}{XY} = \frac{CD}{YZ} = \frac{DA}{ZW}\)

Theorems

Similarity Theorem
Proportionality of Corresponding Sides

Suitable Grade Level

Grades 8-10