C091 · Lenses & ReuleauxISO 128 · 1:1
Pointed Gothic Window — composite figure at 1:1 scale with dimensions, area 42.76 cm²
A = b·h + b²·(π/3 − √3/4)

High school (grades 11–12) · TypeLab 2D

Pointed Gothic Window

Pointed Gothic Window: a composite plane figure made of a circle of radius 5.6 cm, intersected with a circle of radius 5.6 cm, minus a rectangle 8 × 6.4 cm, joined with a rectangle 5.6 × 4.2 cm. It is a classic high school (grades 11–12) geometry problem (“Lenses & Reuleaux”). The net area is 42.76 cm² and the total perimeter is 25.73 cm.

Certified measurements (1:1 scale)

Net area
42.76 cm²
Total perimeter
25.73 cm
Bounding box
5.6 × 9.05 cm
Basic shapes
4
Open in TypeLab 2D

Step-by-step decomposition

  1. 1.Basecircle of radius 5.6 cm98.52 cm²
  2. 2.∩circle of radius 5.6 cm98.52 cm²
  3. 3.−rectangle 8 × 6.4 cm51.2 cm²
  4. 4.+rectangle 5.6 × 4.2 cm23.52 cm²

Area of each basic shape before the Boolean composition.

How to find the area

Area formula: A = b·h + b²·(π/3 − √3/4)

The parts overlap or intersect, so the net area (42.76 cm²) comes from the exact Boolean operation rather than from a plain sum of the part areas.

Editable in PowerPoint & Office

The .PPTX file contains native DrawingML shapes: outlines, dimensions and labels stay separate objects you can recolor and edit in PowerPoint, Keynote and Google Slides. The .SVG file is pure vector art at 1:1 scale on an A4 sheet, ready for print, LaTeX and textbook layout.

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