document.write( "Question 310277: For what value of a is the graph of 5y = ax + 7 perpendicular to the
\n" ); document.write( "graph of by + 3x = 12? \n" ); document.write( "

Algebra.Com's Answer #221880 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
Put both lines in slope-intercept form, $\"y=mx%2Bb\"$
\n" ); document.write( " $\"5y=ax%2B7\"$
\n" ); document.write( " $\"y=%28a%2F5%29x%2B7%2F5\"$
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\n" ); document.write( " $\"by%2B3x=12\"$
\n" ); document.write( " $\"by=-3x%2B12\"$
\n" ); document.write( " $\"y=-%283%2Fb%29x%2B12%2Fb\"$
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\n" ); document.write( "Perpendicular lines have slopes that are negative reciprocals,
\n" ); document.write( " $\"m1%2Am2=-1\"$
\n" ); document.write( " $\"%28a%2F5%29%28-%283%2Fb%29%29=-1\"$
\n" ); document.write( " $\"%283a%29%2F%285b%29=1\"$
\n" ); document.write( " $\"3a=5b\"$
\n" ); document.write( " $\"highlight_green%28a=%285%2F3%29b%29\"$ \n" ); document.write( "

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