document.write( "Question 114898This question is from textbook Beginning Algebra
\n" ); document.write( ": This is a problem from Section 8.1 on page 687. I cannot think backwards, which is what I believe I need to do. The problem is as follows:\r
\n" ); document.write( "\n" ); document.write( "Find values for m and b in the following system so that the solution to the system is (-3,4).\r
\n" ); document.write( "\n" ); document.write( "5x + 7y = b\r
\n" ); document.write( "\n" ); document.write( "mx + y = 22\r
\n" ); document.write( "\n" ); document.write( "Please help! Thank you!! \n" ); document.write( "
Algebra.Com's Answer #83568 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Find values for m and b in the following system so that the solution to the system is (-3,4)\r
\n" ); document.write( "\n" ); document.write( "They want you find both equations of a two-equation system\r
\n" ); document.write( "\n" ); document.write( "Find the 1st equation:
\n" ); document.write( "5x + 7y = b
\n" ); document.write( ":
\n" ); document.write( "Find b by using x,y coordinates given -3, 4
\n" ); document.write( "5(-3) + 7(4) = b
\n" ); document.write( "-15 + 28 = b
\n" ); document.write( "b = + 13
\n" ); document.write( ":
\n" ); document.write( "Find the slope (m): using y = mx + 13, using the given coordinates again
\n" ); document.write( "y = mx + b
\n" ); document.write( "4 = m(-3) + 13
\n" ); document.write( "4 = -3m + 13
\n" ); document.write( "3m = 13 - 4
\n" ); document.write( "3m = 9
\n" ); document.write( "m = +3
\n" ); document.write( ":
\n" ); document.write( "the 1st equation: y = 3x + 13; (m = +3 and b = +13)
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\n" ); document.write( "Find the 2nd equation:
\n" ); document.write( "mx + y = 22
\n" ); document.write( "Find the slope (m) using the given coordinates x,y; -3,4
\n" ); document.write( "m(-3) + 4 = 22
\n" ); document.write( "-3m = 22 - 4
\n" ); document.write( "-3m = 18
\n" ); document.write( "m = 18/-3
\n" ); document.write( "m = -6
\n" ); document.write( ":
\n" ); document.write( "Find b in the 2nd equation, using the given coordinates for x & y again
\n" ); document.write( "y = mx + b
\n" ); document.write( "4 = -6(-3) + b
\n" ); document.write( "4 = 18 + b
\n" ); document.write( "4 -18 = b
\n" ); document.write( "b = -14
\n" ); document.write( ":
\n" ); document.write( "The 2nd equation: y = -6x - 14; (m =- 6 and b = -14)
\n" ); document.write( ":
\n" ); document.write( "If you graphed these two equations, you would find that they intersect at the given coordinates of -3,4
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\n" ); document.write( "\"+graph%28+300%2C+200%2C+-6%2C+5%2C+-10%2C+10%2C+-6x-14%2C+3x%2B13%29+\"
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\n" ); document.write( "Did this make sense? Hope it did.
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