Question 1062463
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There are two different ways to tackle this problem:

1. Factoring and using the principle of zero factors.
2. Using the principle of square roots.

First way:

{{{4x^2-25}}}{{{""=""}}}{{{0}}}

Factor the left side as a difference of squares

{{{(2x)^2-5^2}}}{{{""=""}}}{{{0}}}

{{{(2x-5)(2x+5)}}}{{{""=""}}}{{{0}}}

Since the product of (2x-5) and (2x+5) equals zero,
one of them must equal to 0.

{{{2x-5}}}{{{""=""}}}{{{0}}}; {{{2x+5}}}{{{""=""}}}{{{0}}}
  {{{2x}}}{{{""=""}}}{{{5}}};    {{{2x}}}{{{""=""}}}{{{-5}}}

Divide both sides by 2

   {{{x}}}{{{""=""}}}{{{5/2}}};    {{{x}}}{{{""=""}}}{{{-5/2}}}

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Second way: Using the principle of square roots.

{{{4x^2-25}}}{{{""=""}}}{{{0}}}

Add 25 to both sides:

{{{4x^2}}}{{{""=""}}}{{{25}}}

Divide both sides by 4:

{{{4x^2/4}}}{{{""=""}}}{{{25/4}}}

{{{cross(4)x^2/cross(4)}}}{{{""=""}}}{{{25/4}}}

{{{x^2}}}{{{""=""}}}{{{25/4}}}

Use the principle of square roots:

{{{x}}}{{{""=""}}}{{{"" +- sqrt(25/4)}}}

{{{x}}}{{{""=""}}}{{{"" +- 5/2)}}}

Which is easier?

Edwin</pre></b></font>