document.write( "Question 943443: Show that the linear function f defined by
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Algebra.Com's Answer #575183 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
f(x) is even when f(-x) = f(x) for all x in the domain.\r
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\n" ); document.write( "\n" ); document.write( "f(x) = mx + b\r
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\n" ); document.write( "\n" ); document.write( "f(-x) = m(-x) + b\r
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\n" ); document.write( "\n" ); document.write( "f(-x) = -mx + b\r
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\n" ); document.write( "\n" ); document.write( "Set f(-x) equal to f(x)\r
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\n" ); document.write( "\n" ); document.write( "f(-x) = f(x)\r
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\n" ); document.write( "\n" ); document.write( "-mx + b = mx + b\r
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\n" ); document.write( "\n" ); document.write( "-mx + b-b = mx + b-b ... Subtract b from both sides.\r
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\n" ); document.write( "\n" ); document.write( "-mx = mx\r
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\n" ); document.write( "\n" ); document.write( "-mx+mx = mx+mx ... Add mx to both sides.\r
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\n" ); document.write( "\n" ); document.write( "0 = mx+mx\r
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\n" ); document.write( "\n" ); document.write( "0 = 2mx\r
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\n" ); document.write( "\n" ); document.write( "2mx = 0\r
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\n" ); document.write( "\n" ); document.write( "2mx = 0 means m = 0 (since x is any number, it's not always 0, so m has to be zero)
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