document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=424673>Question 424673</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If P(A or B) = 0.8, P(A)= 0.1 and P(B) = 0.9 determine P(A and B) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #295967 by </B><A HREF=/tutors/aboutme.mpl?userid=linh117><B>linh117(31)</B></A><img src=\"/images/stars/stars-07.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=linh117><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=295967\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> P(A or B)= P(A) + P(B) - P(A and B)<BR>\n" );
document.write( "0.8=0.1+0.9-x\r<BR>\n" );
document.write( "\n" );
document.write( "Since x is on the right-hand side of the equation, switch the sides so it is on the left-hand side of the equation.<BR>\n" );
document.write( "0.1+0.9-x=0.8\r<BR>\n" );
document.write( "\n" );
document.write( "Add 0.9 to 0.1 to get 1.<BR>\n" );
document.write( "1-x=0.8\r<BR>\n" );
document.write( "\n" );
document.write( "Since 1 does not contain the variable to solve for, move it to the right-hand side of the equation by subtracting 1 from both sides.<BR>\n" );
document.write( "-x=-1+0.8\r<BR>\n" );
document.write( "\n" );
document.write( "Add 0.8 to -1 to get -0.2.<BR>\n" );
document.write( "-x=-0.2\r<BR>\n" );
document.write( "\n" );
document.write( "Multiply each term in the equation by -1.<BR>\n" );
document.write( "-x*-1=-0.2*-1\r<BR>\n" );
document.write( "\n" );
document.write( "Multiply -x by -1 to get x.<BR>\n" );
document.write( "x=-0.2*-1\r<BR>\n" );
document.write( "\n" );
document.write( "Multiply -0.2 by -1 to get 0.2.<BR>\n" );
document.write( "x=0.2 </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );