{VERSION 5 0 "IBM INTEL NT" "5.0" } {USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 0 1 0 0 0 0 1 }{CSTYLE "" -1 256 "" 0 1 0 128 0 1 0 0 0 0 0 0 0 0 0 0 } {CSTYLE "" -1 257 "" 0 1 0 128 0 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 258 "" 0 1 0 128 128 1 0 0 0 0 0 0 0 0 0 0 }{CSTYLE "" -1 259 "" 0 1 128 128 128 1 0 0 0 0 0 0 0 0 0 0 }{PSTYLE "Normal" -1 0 1 {CSTYLE "" -1 -1 "Times" 1 12 0 0 0 1 2 2 2 2 2 2 1 1 1 1 }1 1 0 0 0 0 1 0 1 0 2 2 0 1 }{PSTYLE "Heading 1" -1 3 1 {CSTYLE "" -1 -1 "Times" 1 18 0 0 0 1 2 1 2 2 2 2 1 1 1 1 }1 1 0 0 8 4 1 0 1 0 2 2 0 1 }{PSTYLE "Heading 2 " -1 4 1 {CSTYLE "" -1 -1 "Times" 1 14 0 0 0 1 2 1 2 2 2 2 1 1 1 1 }1 1 0 0 8 2 1 0 1 0 2 2 0 1 }} {SECT 0 {PARA 0 "" 0 "" {TEXT 257 50 "High School Modules > Algebra by Gregory A. Moore " }}{PARA 3 "" 0 "" {TEXT -1 4 " " }{TEXT 256 24 "Solving Linear Equations" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 " " 0 "" {TEXT -1 45 "Learning the steps to solve linear equations." }} {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT 258 153 "[Direct ions : Execute the Code Resource section first. Although there will be no output immediately, these definitions are used later in this works heet.]" }}{SECT 0 {PARA 4 "" 0 "" {TEXT -1 4 "Code" }}{EXCHG {PARA 0 " > " 0 "" {MPLTEXT 1 0 9 "restart; " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 81 "AddBothSides := proc( expr, a )\n lhs(expr) + a \+ = rhs( expr) + a; \n end proc:" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 104 "MultBothSides := proc( expr, a )\n simplify(lhs(expr) * \+ a) = simplify( rhs( expr) * a) ; \n end proc:" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 112 "SimplifyBothSides := proc( expr )\n simplify ( factor( lhs(expr) )) = simplify( factor( rhs(expr) ));\nend proc:" } }}}{SECT 0 {PARA 4 "" 0 "" {TEXT -1 9 "Example 1" }}{EXCHG {PARA 0 "> \+ " 0 "" {MPLTEXT 1 0 14 "17*x - 5 = 29;" }}}{PARA 0 "" 0 "" {TEXT -1 113 "\nLets get rid of the number term, -5, on the same side as the x term, by adding its opposite, +5 \nto both sides." }}{EXCHG {PARA 0 " > " 0 "" {MPLTEXT 1 0 20 "AddBothSides( %, 5);" }}}{PARA 0 "" 0 "" {TEXT -1 53 "\nNow, we multiply both sides by the reciprocal of 17." } }{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 24 "MultBothSides( %, 1/17);" } }}{PARA 0 "" 0 "" {TEXT -1 80 "\nWe are done. We found the answer. Map le can also solve the problem in one step." }}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 27 "solve( 17*x - 5 = 29, x) ;" }}}}{SECT 0 {PARA 4 " " 0 "" {TEXT -1 9 "Example 2" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 19 "1/7*x+1 = 1/4*x-35;" }}}{PARA 0 "" 0 "" {TEXT -1 109 "\nLets first clear the denominators by multiplying both sides by the LCM, 28, of \+ the \n denominators, 7 and 4." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 22 "MultBothSides( %, 28);" }}}{PARA 0 "" 0 "" {TEXT -1 68 "\nNow le ts get rid of the smaller x term, so only one x term remains." }} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 23 "AddBothSides( %, -4*x);" }}} {PARA 0 "" 0 "" {TEXT -1 152 "\nWe still have two purely number terms, 28 and 980. Lets eliminate the one, -980, on the same side as the \nx term, by adding its opposite to both sides." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 22 "AddBothSides( %, 980);" }}}{PARA 0 "" 0 "" {TEXT -1 87 "\nThere is one final step : to change 3x into x by multiplying \+ y by the reciprocal, 1/3." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 23 "MultBothSides( %, 1/3);" }}}{PARA 0 "" 0 "" {TEXT -1 79 "\nWe are don e. We found he answer. Maple can also solve the problem in one step." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 32 "solve( 1/7*x+1 = 1/4*x-35, x) ;" }}}{PARA 0 "" 0 "" {TEXT -1 186 "\nNote that we added to both \+ sides twice in a row. First we added -4x, then we added 980. Why not \+ \ndo both steps at once? Here is how this problem would look if we spe d it up in this way." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 19 "1/7* x+1 = 1/4*x-35;" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 22 "MultBoth Sides( %, 28);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 30 "AddBothSi des( %, -4*x + 980 );" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 23 "Mu ltBothSides( %, 1/3);" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}{SECT 0 {PARA 4 "" 0 "" {TEXT -1 9 "Example 3" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 42 "(3/5)*(x - 7/3) = (1/9)*x + 3*(4*x - 5/2);" }}}{PARA 0 "" 0 "" {TEXT -1 236 "Note that Maple automatically distributes and \+ combines like terms on both sides. \n\nHowever, there is still more to do. Lets first clear the denominators by multiplying\nboth sides by t he LCM, 90, of the various denominators, 2, 5 and 9." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 22 "MultBothSides( %, 90);" }}}{PARA 0 "" 0 " " {TEXT -1 68 "\nNow lets get rid of the smaller x term, so only one x term remains." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 24 "AddBothSid es( %, -54*x);" }}}{PARA 0 "" 0 "" {TEXT -1 147 "\nWe still have two p urely number terms. Lets eliminate the one, -675, on the same side as \+ the \nx term, by adding its opposite, +675, to both sides." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 22 "AddBothSides( %, 675);" }}}{PARA 0 "" 0 "" {TEXT -1 93 "\nThere is one final step : to change 1036x into \+ x by multiplying y by the reciprocal, 1/1036." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 26 "MultBothSides( %, 1/1036);" }}}{PARA 0 "" 0 "" {TEXT -1 80 "\nWe are done. We found the answer. Maple can also solve \+ the problem in one step." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 55 " solve( (3/5)*(x - 7/3) = (1/9)*x + 3*(4*x - 5/2), x) ;" }}}}{SECT 0 {PARA 4 "" 0 "" {TEXT -1 9 "Example 4" }}{PARA 0 "" 0 "" {TEXT -1 122 "These same methods will be used to solve more advanced problems, late r. For example, if we have\nan expression like this :\n" }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 18 "3/(x-2) + 5/x = 7;" }}}{PARA 0 "" 0 "" {TEXT -1 88 "\nWe can multiply both sides by the LCM of the algeb raic expressions in the denominators." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 29 "MultBothSides( %, (x-2)*x );\n" }}}{PARA 0 "" 0 "" {TEXT -1 98 "\nIn this case, we can move everything to one side by add ing the opposite of (8x-10) to both sides." }}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 30 "AddBothSides( %, -(8*x -10) );" }}}{PARA 0 "" 0 "" {TEXT -1 28 "\nWe can simplify both sides." }}{EXCHG {PARA 0 "> " 0 " " {MPLTEXT 1 0 21 "SimplifyBothSides(%);" }}}{PARA 0 "" 0 "" {TEXT -1 98 "\nSince this is not a linear equation, we need to use other method s. We'll discuss this more later." }}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 9 "solve(%);" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 0 "" }}}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}{PARA 0 "" 0 "" {TEXT 259 35 "\n \251 2002 Wa terloo Maple Inc" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}{MARK "0 0" 8 } {VIEWOPTS 1 1 0 1 1 1803 1 1 1 1 }{PAGENUMBERS 0 1 2 33 1 1 }