+0  
 
0
34
1
avatar

Sqaure root of l(l-5)=6

 
Guest Aug 6, 2017
social bar
Sort: 

1+0 Answers

 #1
avatar+4155 
+1

Is this your question?

 

\(\sqrt{l(l-5)}=6\)

                                                   Square both sides of the equation.

\(\sqrt{l(l-5)}^2=6^2 \\~\\ l(l-5)=36\)

                                                   Distribute the  l  to both terms in parenthesees.

\(l^2-5l=36\)

                                                   Subtract  36  from both sides of the equation.

\(l^2-5l-36=0\)

                                                   Use the quadratic formula to solve for  l  .

\(l=\frac{-(-5)\pm\sqrt{(-5)^2-4(1)(-36)}}{2(1)} \\~\\ l=\frac{5\pm\sqrt{25+144}}{2} \\~\\ l=\frac{5\pm13}{2} \\~\\ \begin{array} \ l=\frac{5+13}{2}\qquad &\text{or}&\qquad l=\frac{5-13}{2}\\~\\ l=9&\text{or}&\qquad l=-4 \end{array}\)

 
hectictar  Aug 7, 2017

15 Online Users

avatar
avatar
We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  See details