document.write( "Question 989749: what is the equation in standard form of a perpendicular line that's passes through (5,1)._______y+4=-4(x-2)this equation is the beginning problem u use to answer the problem pls help \n" ); document.write( "
Algebra.Com's Answer #609978 by KMST(5328)\"\" \"About 
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We are asked to write an equation in standard form for line that passes through point (5,1),
\n" ); document.write( "and is perpendicular to a line with the equation \"y%2B4=-4%28x-2%29\"\r
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\n" ); document.write( "\n" ); document.write( "The equation of a line can be written in many forms.
\n" ); document.write( "Depending on the information given,
\n" ); document.write( "we may find it easier to start by writing the equation in one or another form.
\n" ); document.write( "Then, if we get the equation of a line in any other form,
\n" ); document.write( "we can always find an equivalent equation in standard form.
\n" ); document.write( "The standard form of the equation of a line is \"Ax%2BBy=C\" ,
\n" ); document.write( "with \"A\" , \"B\" and \"C\" being any real numbers,
\n" ); document.write( "except that \"A\" and \"B\" cannot be both zero at the same time.\r
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\n" ); document.write( "\n" ); document.write( "If we know a point \"P%28h%2Ck%29\" on a line,
\n" ); document.write( "and we know that the slope of that line is \"m\" ,
\n" ); document.write( "we can write an equation for that line in point-slope form as
\n" ); document.write( "\"y-k=m%28x-h%29\" .
\n" ); document.write( "For example, \"y%2B4=red%28-4%29%28x-2%29\",--->\"y-%28green%28-4%29%29=red%28-4%29%28x-2%29\" is the equation of a line with slope \"red%28-4%29\" that passes through point \"P%282%2Cgreen%28-4%29%29\" .\r
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\n" ); document.write( "\n" ); document.write( "For perpendicular lines, if they both have slopes,
\n" ); document.write( "the product of their slopes is \"-1\" .
\n" ); document.write( "That can also be said as \"their slopes are negative reciprocals (or opposite reciprocals) of each other.\"
\n" ); document.write( "So for a line has a slope of \"red%28-4%29\",
\n" ); document.write( "the slope for any perpendicular line is \"1%2F4\" .\r
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\n" ); document.write( "\n" ); document.write( "So we are looking for the equation of a line with slope \"%281%2F4%29\" that passes through point (5,1).
\n" ); document.write( "The point-slope form for that line (based on that point) is
\n" ); document.write( "\"y-1=%281%2F4%29%28x-5%29\" .
\n" ); document.write( "From there, we use what we know of algebra to transform that equation into an equivalent equation in standard form:
\n" ); document.write( "\"y-1=%281%2F4%29%28x-5%29\" ---> \"4%28y-1%29=%284%29%281%2F4%29%28x-5%29\" ---> \"4y-4=%281%29%28x-5%29\" ---> \"4y-4=x-5\" ---> \"-x%2B4y-4=-5\" ---> \"-x%2B4y=-5%2B4\"
\n" ); document.write( "---> \"highlight%28-x%2B4y=-1%29\"<--->\"highlight%28x-4y=1%29\" .\r
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\n" ); document.write( "\n" ); document.write( "NOTE: \"x-4y=1\" is not the only standard form equation for that line.
\n" ); document.write( "It may be the simplest or most elegant answer,
\n" ); document.write( "although some may like \"-x%2B4y=-1\" , or \"%281%2F4%29x%2By=1%2F4\" ,
\n" ); document.write( "but multiplying both sides of the equal sign times any non-zero number gives you an equivalent equation,
\n" ); document.write( "so there is an infinite number of equation in standard form for any line.
\n" ); document.write( "In our case, multiplying times \"1\" for example, we get
\n" ); document.write( "\"10x-40y=10\" , which is another equivalent equation in standard form.
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