Basic Proportionality Theorem - STD 9 - Teaching Aid

Basic Proportionality Theorem • Interactive Demo

Basic Proportionality Theorem

A line parallel to one side of a triangle divides the other two sides proportionally

Theorem Statement

If a line parallel to one side of a triangle intersects the other two sides, then it divides those sides in the same ratio.

p / a = r / b
q / a = s / b
Interactive Figure
Position of Parallel Line 0.50
STEP-BY-STEP EXPLANATION

How it works

STEP 1/7

Live Ratio Verification

First Ratio
p / a = 0.500
Second Ratio
q / a = 0.500
Both ratios are equal — Theorem verified!
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