The equation is .
Add 7 to each side.
.
To check the solution, substitute the value of in the original equation, .
This statement is true, so the solution of equation is 20.
The value of .
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.![\"\"](\"/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=04955c42a079d196ea052644705dcf5b.png\")
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.![\"\"](\"http://www.mathskey.com/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=dda2a8c1f3d1c3b0936203bd534e57f6.png\")
in the original equation, ![\"\"](\"http://www.mathskey.com/test/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=a63cf55d6ced15b36b7fdde023ceb6ed.png\")
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.![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/solution.JPG\")
.