Math Problem Statement

Week 12: Perimeter and Area of an Irregular Figure. Look at the figure below. Notice the semicircle on the left, and the adjacent right triangle. The units of measure in the figure are centimeters. a) What is the measure (in centimeters) of each of the two legs of the right triangle? b) How can those measures be used to find the length of the hypotenuse? c) Find the length of the hypotenuse, assuming all lengths are given in centimeters.

Solution

The question on the image concerns finding the perimeter and area of an irregular figure, which includes a semicircle and a right triangle.

Problem Breakdown:

  1. Semicircle: The diameter is given as 8 cm, making the radius r=82=4r = \frac{8}{2} = 4 cm.
  2. Right Triangle: The base of the triangle is 4 cm, and its height (same as the diameter of the semicircle) is 8 cm.

Solutions:

Part (a)

Determine the measures of the two legs of the right triangle:

  • One leg: 4 cm (base of the triangle).
  • Other leg: 8 cm (height of the triangle, same as the diameter of the semicircle).

Part (b)

Explain how to use these measures to find the hypotenuse:

  • Use the Pythagorean theorem, c=a2+b2c = \sqrt{a^2 + b^2}, where aa and bb are the legs of the triangle, and cc is the hypotenuse.

Part (c)

Calculate the hypotenuse: c=42+82=16+64=80=458.94 cmc = \sqrt{4^2 + 8^2} = \sqrt{16 + 64} = \sqrt{80} = 4\sqrt{5} \approx 8.94 \text{ cm}

Would you like further details on the area or perimeter of the combined figure?

Follow-Up Questions:

  1. How would you calculate the area of the semicircle?
  2. What is the perimeter of the irregular figure?
  3. How is the hypotenuse used in perimeter calculations for composite shapes?
  4. What is the total area of the figure, combining the semicircle and the triangle?
  5. How would the calculations change if the triangle's base were altered?

Tip: Remember to use consistent units throughout calculations for accuracy.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Geometry
Pythagorean Theorem
Area and Perimeter of Composite Figures

Formulas

Pythagorean theorem: c = √(a^2 + b^2)
Area of a semicircle: (πr^2)/2

Theorems

Pythagorean Theorem

Suitable Grade Level

Grade 7-9