Right Triangle with Proportional Measures, and a Rhombus
Pencil right triangle labelled with fractional lengths beside a rhombus on one base
A faint pencil sheet showing a triangle at the left and a rhombus (diamond) at the right, both resting on one horizontal base line. The editor names the left figure a right triangle whose sides carry numeric measures - 3, 2 2/5, 4 and the value 144/25 - so the geometry is tied to a proportional calculation of its parts. The heading number 81 is written at the top.
On this page
Right triangle and rhombus on a shared base
The left figure is the right triangle named in the caption, standing on a ruled horizontal base line. A rhombus is drawn to its right on the same base, built up symmetrically from triangular halves.
Fractional lengths a, b, d
The sides of the right triangle are annotated with numbers and fractions: a - 3, 2 2/5, 4 - b, and d - 144/25, with the further series 1 4/5, 5, 3 1/5. These give the proportional measures of the segments and the squared quantity 144/25.