document.write( "Question 572056: Find the equation of the line in standard form that passes through (-7,5) and is perpendicular to -4x+3y=13.\r
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document.write( "So far I have:
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document.write( "-4x+4x+3y=4x+13
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document.write( "3y/3=4x/3+13/3
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document.write( "y=4/3x+13/3. \r
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document.write( "Am I right at all? And if so, where do I go from here? \n" );
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Algebra.Com's Answer #368277 by Theo(13342)![]() ![]() You can put this solution on YOUR website! the line is perpendicular to is: \n" ); document.write( "-4x + 3y = 13 \n" ); document.write( "you have to put this equation into slope intercept form. \n" ); document.write( "add 4x to both sides of this equation to get: \n" ); document.write( "3y = 4x + 13 \n" ); document.write( "divide both sides of this equation by 3 to get: \n" ); document.write( "y = (4/3)x + (13/3) \n" ); document.write( "that gets you the equation of the line that you have to be perpendicular to into slope intercept form. \n" ); document.write( "the general of slope intercept form is: \n" ); document.write( "y = mx + b \n" ); document.write( "m equals the slope. \n" ); document.write( "b equals the y intercept. \n" ); document.write( "the slope of the line formed by this equation is (4/3) \n" ); document.write( "for a line to be perpendicular to it, the slope of that line has to be the negative reciprocal of it. \n" ); document.write( "the negative reciprocal of (4/3) is equal to -(3/4). \n" ); document.write( "that the slope of your new line. \n" ); document.write( "the general form of your new line becomes: \n" ); document.write( "y = -(3/4)x + b \n" ); document.write( "your new line goes through the point (-7,5) \n" ); document.write( "replace x with -7 and y with 5 in the slope intercept form of your new line to get: \n" ); document.write( "5 = -(3/4)(-7) + b \n" ); document.write( "solve for b. \n" ); document.write( "simplify the equation to get: \n" ); document.write( "5 = (21/4) + b \n" ); document.write( "subtract (21/4) from both sides of this equation to get: \n" ); document.write( "5 - (21/4) = b \n" ); document.write( "simplify to get: \n" ); document.write( "-1/4 = b \n" ); document.write( "that's your answer in fraction form. \n" ); document.write( "the equation of the line perpendicular to your original line and passing through the point (-7,5) is: \n" ); document.write( "y = -(3/4)x - (1/4) \n" ); document.write( "let's see if that's true. \n" ); document.write( "the graph of your 2 lines is shown below: \n" ); document.write( " \n" ); document.write( "they look perpendicular to each other. \n" ); document.write( "their y intercepts should be: \n" ); document.write( "original equation y intercept = (13/3) \n" ); document.write( "perpendicular equation y intercept = -(1/4) \n" ); document.write( "i placed horizontal lines as y = (13/3) and -(1/4) to see if the y intercepts are correct. \n" ); document.write( "that graph looks like this: \n" ); document.write( " \n" ); document.write( "all that's required to see if if the perpendicular line passes through the point (-7,5). \n" ); document.write( "i placed a vertical line at x = -7 and a horizontal line at y = 5 to see if that point is on the perpendicular line. \n" ); document.write( "that graph is shown below: \n" ); document.write( " \n" ); document.write( "since the line of the perpendicular equation intersects with the lines x = -7 and y = 5, this means that the point (-7,5) is on the line of the perpendicular equation. \n" ); document.write( "everything check out, so the equation of the line perpendicular to the original line is: \n" ); document.write( "y = -(3/4)x - (1/4) \n" ); document.write( " \n" ); document.write( " |