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## Algebra 1

### Unit 13: Lesson 4

Introduction to factoring

# GCF factoring introduction

## Problem

Todor was trying to factor 10, x, squared, minus, 5, x, plus, 15. He found that the greatest common factor of these terms was 5 and made an area model:
An area model for a rectangle with a height of five and an unknown width. The rectangle is broken into three rectangles to isolate each term in the width. The first rectangle has a height of five and an area of ten x squared. The second rectangle has a height of five and an area of negative five x. The third rectangle has a height of five and an area of fifteen.
What is the width of Todor's area model?
start text, W, i, d, t, h, end text, equals
Stuck?
Stuck?