Scale Drawings and Geometric Constructions: Math Unit 4, Grade 7 (Letters & Devotion)

Description

Scale Drawings and Geometric Constructions is Unit 4 of Mathematics 7: Proportional Reasoning and Rational Number Systems (Grade 7), the Letters & Devotion Math course, complete in one printable PDF: 10 lessons, the unit check-up and the answer key, 60 pages.

• Scale factor as a constant of proportionality applied to a single length
• The relationship between a linear scale factor and the resulting area, computed via actual lengths rather than by squaring the scale factor directly
• The multiplicative (not additive) relationship between linear scale factor and area scale factor
• The defining property of a scaled copy: every corresponding length pair shares the same constant ratio
• Combining two scale ratios (original-to-actual and actual-to-new) to reproduce a figure at a new scale
• Deriving a scale factor between two representations with no scale given, using measured corresponding distances
• The triangle inequality as the condition for SSS construction to succeed
• The conditions (SSS, SAS, ASA) under which a triangle is uniquely determined, versus conditions that permit more than one triangle or none
• Generalizing the existence/uniqueness rule for triangles beyond the SSS/SAS/ASA cases explicitly taught
• Discriminating between scale-factor problems and triangle-construction problems based on structural features of the prompt, not its position in the unit

Every lesson is written for a parent with no teaching background: it opens with a short script to read aloud, names the specific wrong idea a student is likely to reach for and how to correct it, and closes with a practice sheet you may copy for your household. Scripture references are King James Version throughout. Black-and-white, 8.5 x 11 in. The whole year of this course is also in this store as a single book.

AI note: The written content of this resource was drafted with AI tools, then reviewed and edited by the author.