![\"\"](\"/userfiles/image/steps_images/step1.JPG\")
\
The equation is ![\"\"](\"/MathKey/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=15ac7a91612d4c6a773965d1d0c96e50.png\")
.
Observe the equation and think of the equation as a question.
\Which number minus 20 equals 15?
\The number is 35
\![\"\"](\"/userfiles/image/steps_images/step2.JPG\")
Check:
\To check the solution, substitute ![\"\"](\"/MathKey/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=9d44cbca97d1c973d595853caf5cea4e.png\")
in original equation.
![\"\"](\"/MathKey/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=c0a14538e25cc9780c8bad405b4ae3ca.png\")
![\"\"](\"/MathKey/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=c3e263fe4a43896dddbb604ee9a348a4.png\")
(Subtract: ![\"\"](\"/MathKey/fckeditor/editor/plugins/fckeditor_wiris/integration/showimage.php?formula=9bd1bb7b82faf45b47eab221b4f706cc.png\")
)
Compare the values, the equation is true.
\![\"\"](\"/userfiles/image/steps_images/solution.JPG\")
The value of .