document.write( "Question 51217This question is from textbook Prentice Hall Mathematics Algebra 2
\n" ); document.write( ": write an equation for each line. Then Graph thr line
\n" ); document.write( "through (-3,-1) and perpendicular to $\"y=-%282%2F5%29x-4\"$ \n" ); document.write( "

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We know the slope of the first line is $\"-%282%2F5%29\"$ because its equation is in the form y=mx+b. By definition, the slopes of two perpendicular lines are negative reciprocals of each other. So the negative reciprocal of $\"-2%2F5\"$ becomes $\"5%2F2\"$ , which is the slope to the perpendicular line. We now have the slope and a point (-3,-1) for the perpendicular line, so we can compute it via substitution into $\"y=mx%2Bb\"$ , thusly: $\"-1=%285%2F2%29%2A%28-3%29%2Bb\"$ . This reduces to $\"-1=-15%2F2%2Bb\"$ . Now we add $\"15%2F2\"$ to both sides to produce $\"13%2F2=b\"$ . That means the equation for the perpendicular line is $\"y=%285%2F2%29x%2B13%2F2\"$ .
\n" ); document.write( " $\"graph%28300%2C300%2C-12%2C1%2C-6%2C8%2C%28-2%2F5%29x-4%2C5x%2F2%2B13%2F2%29\"$ \n" ); document.write( "

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