Question 130869

*[Tex \LARGE (2x-3)^2=25] Start with the given equation




*[Tex \LARGE 2x-3=\pm sqrt{25}] Take the square root of both sides





*[Tex \LARGE 2x-3=\pm 5] Take the square root of 25 to get 5




*[Tex \LARGE 2x=3\pm 5] Add 3 to both sides.



 Break down the expression into two parts:




 <pre>

 *[Tex \LARGE 2x=3+5]  <font size="6">or</font>  *[Tex \LARGE 2x=3-5]

 </pre>


 Now combine like terms for each expression:

 <pre>

 *[Tex \LARGE 2x=8]  <font size="6">or</font>   *[Tex \LARGE 2x=-2]   </pre>


Divide both sides by 2 to isolate x

 <pre>

 *[Tex \LARGE x=4]  <font size="6">or</font>   *[Tex \LARGE x=-1]   </pre>



-----------------------------------

Answer:

So our solution is

 <pre>

*[Tex \LARGE x=4]  <font size="6">or</font>   *[Tex \LARGE x=-1]
 </pre>


 Notice when we graph the equations {{{y=(2x-3)^2}}} and {{{y=25}}}  we get:


{{{drawing(500, 500, -7, 13, -10, 30,
graph( 500, 500, -7, 13, -10, 30, (2x-3)^2,25)
)}}} graph of  {{{y=(2x-3)^2}}} (red) and {{{y=25}}} (green)




Here we can see that the two equations intersect at x values of {{{x=-2}}} and {{{x=4}}}, so this verifies our answer.