\n" );
document.write( "Hi, \n" );
document.write( "solving by combining like terms & isolating the variable a on one side of equation \n" );
document.write( " 9 = -7 -2a +a |combining like terms on the right side \n" );
document.write( " 9 = -7 -a | adding a to both sides of the equation \n" );
document.write( " a + 9 = -7 | subtracting 9 to both sides of the equation \n" );
document.write( " a = -16