Pythagorean theorem: squares with inscribed circles
Building one square from two, shown with square a b c d and inscribed circles
Leonardo sets himself the problem of making a single square out of two different squares and promises to show how much the result grows beyond each of the originals. A central pen diagram gives the figure of the Pythagorean theorem, drawing two adjoining squares each holding an inscribed circle, together with a smaller square (labelled with m and n) at the corner. He describes a square a b c d that would 'clothe' or surround the larger square together with the smaller one set above it.
On this page
Making one square out of two different squares
The opening note states the task: to construct a single square from two squares of different size, and to demonstrate how much larger it becomes than either of the two. It frames the page as a proof about combining squares.
Square a b c d surrounding a larger and a smaller square
The labelled figure names points b a n m c d and treats a b c d as a square that would enclose the larger opposing square together with the smaller one placed above it. Two larger squares each carry an inscribed circle, with a small square marked m and n at the join. It is Leonardo's construction of the Pythagorean relation among the squares.