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# Using Square Roots to Solve Quadratic Equations

Author: Rachel Kaplan
##### Description:

Objectives for this learning packet include
-Review the idea of a square root and what it means
-When given a quadratic equation where b=0, solve using square roots

With a handy lesson, become familiar with square roots and how to use them to solve some basic quadratic equations.

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Tutorial

## Basics of Square Roots    ## Table of Perfect Squares

02 = 0
12 = 1
22 = 4
32 = 9
42 = 16
52 = 25
62 = 36
72 = 49
82 = 64
92 = 81
102 = 100
112 = 121
122 = 144
132 = 169
142 = 196
152 = 225
162 = 256
172 = 289
182 = 324
192 = 361
202 = 400
212 = 441
222 = 484
232 = 529
242 = 576
252 = 625

Here's a handy table of perfect squares if you need an easy reference. Trust me though, soon you'll have many of these memorized!

## Using Square Roots to Solve Quadratic Equations  ## Examples

Try some of these out on your own, and scroll down when you're complete to view the final answers.

1. x2+6 = 87

2. x2-7 = 71

3. 9x2+3 = 84

4. 5x2+7 = 132

5. Challenge: x(x2+4) = 40x