document.write( "Question 931491: Please assist,\r
\n" ); document.write( "\n" ); document.write( "Write the equation of a line perpendicular to the given line but passing through the given point.\r
\n" ); document.write( "\n" ); document.write( "y = -4x - 5; point (0, -1)
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Algebra.Com's Answer #565610 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
The slope of the line represented by \"y=-4x-5\" is \"M=-4\" .
\n" ); document.write( "The slope of a line perpendicular to a line of slope \"M\"} is \"m=-1%2FM\" ,
\n" ); document.write( "so the slope of the line you are looking for is
\n" ); document.write( "\"m=-1%2F%28%28-4%29%29=1%2F4\" .
\n" ); document.write( "The x-coordinate of the point the line passes through is zero, meaning that the point is on the y-axis.
\n" ); document.write( "In other words that point is the y-intercept of the line.
\n" ); document.write( "The equation of a line can be written in the slope-intercept form as
\n" ); document.write( "\"y=mx%2Bb\" when the slope is \"m\" and the y-intercept is \"%22%28+0+%2C+b+%29%22\" ,
\n" ); document.write( "so the equation you are looking for is
\n" ); document.write( "\"highlight%28y=%281%2F4%29x-1%29\"
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\n" ); document.write( "NOTE: For this problem, the point given \"happens to be\" the y-intercept.
\n" ); document.write( "More generally:
\n" ); document.write( "A line of slope \"m\" , passing through a point \"P%28x%5BP%5D%2Cy%5BP%5D%29\"
\n" ); document.write( "can be represented by the equation \"y-y%5BP%5D=m%28x-x%5BP%5D%29\" ,
\n" ); document.write( "and that is called a point-slope form of the equation.
\n" ); document.write( "So, the line you are looking for, passing through (0,-1) can be represented by the equation
\n" ); document.write( "\"y-%28-1%29=%281%2F4%29%28x-0%29\" <---> \"y%2B1=%281%2F4%29x\"
\n" ); document.write( "The equation above is one of the infinite number of equations for the line you are looking for.
\n" ); document.write( "The more popular, one and only, slope-intercept form is the \"y=mx%2Bb\" form that you find when you \"solve for y\" :
\n" ); document.write( "\"y%2B1=%281%2F4%29x\" <---> \"y=%281%2F4%29x-1\" .
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