Difference between revisions of "Square root property"

(Second format)
(Method)
 
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<math>x=\frac{\pm\sqrt{5}-4}{3}</math>
 
<math>x=\frac{\pm\sqrt{5}-4}{3}</math>
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and those are the roots.

Latest revision as of 23:55, 15 May 2014

The square root property is a method for solving quadratic equations.

Method

First we must convert the quadratic to either the form $ax^2=b$ or $(yx+z)^2=w$.

First format

$x^2=18$

take the square root of both sides

$x=\pm\sqrt{18}$

so the roots are $\sqrt{18}$ and $-\sqrt{18}$.

Second format

$(3x+4)^2=5$

take the square root of both sides

$3x+4=\pm\sqrt{5}$

isolate $x$

$x=\frac{\pm\sqrt{5}-4}{3}$


and those are the roots.