Question 1092180
Find the slope of the given line
{{{ x - 7y - 9 = 0 }}}
{{{ 7y = x - 9 }}}
{{{ y = (1/7)*x - 9/7 }}}
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Any line perpendicular to this line has
slope {{{ m[2] = -1/m[1] }}} where
{{{ m[1] = 1/7 }}}
{{{ m[2] = -1/(1/7) }}}
{{{ m[2] = -7 }}}
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(8,-2)
Use the general point-slope formula
{{{ ( y -(-2) ) / ( x - 8 ) = -7 }}}
{{{ ( y + 2 ) / ( x - 8 ) = -7 }}}
{{{ y + 2 = -7*( x - 8 ) }}}
{{{ y + 2 = -7x + 56 }}}
{{{ y = -7x + 54 }}}
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check:
Does the line go through ( 8, -2 ) ?
{{{ -2 = -7*8 + 54 }}}
{{{ -2 = -56 + 54 }}}
{{{ -2 = -2 }}}
OK