document.write( "Question 198824: Let A(-2,4), B(-7,1) and C(-1,-5) be the vertices of a triangle.
\n" ); document.write( "a. Find an equation whose graph is a line that contains the median from A to the midpoint of line segment BC.
\n" ); document.write( "b. Find the length of the median from A to line segment BC.
\n" ); document.write( "c. Find the length of the altitude from A to line segment BC.
\n" ); document.write( "d. Find the area of the traingle ABC.\r
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Algebra.Com's Answer #149323 by solver91311(24713)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "Let A(-2,4), B(-7,1) and C(-1,-5) be the vertices of a triangle.\r
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\n" ); document.write( "\n" ); document.write( "a. Find an equation whose graph is a line that contains the median from A to the midpoint of line segment BC.\r
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\n" ); document.write( "\n" ); document.write( "Use the midpoint formulas to find the midpoint of the segment BC.\r
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\n" ); document.write( "\n" ); document.write( "where and are the coordinates of points B and C. (doesn't matter which is which)\r
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\n" ); document.write( "\n" ); document.write( "Then use the two-point form of the equation of a line to derive the desired equation:\r
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\n" ); document.write( "\n" ); document.write( "Where are the coordinates of point A and are the coordinates of the midpoint derived in the previous step.\r
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\n" ); document.write( "\n" ); document.write( "b. Find the length of the median from A to line segment BC.\r
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\n" ); document.write( "\n" ); document.write( "Use the distance formula:\r
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\n" ); document.write( "\n" ); document.write( "Where are the coordinates of point A and are the coordinates of the midpoint derived in the previous step.\r
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\n" ); document.write( "\n" ); document.write( "c. Find the length of the altitude from A to line segment BC.\r
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\n" ); document.write( "\n" ); document.write( "Step 1. Derive the equation of the line containing segment BC. Use the two-point form of the equation of a line:\r
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\n" ); document.write( "\n" ); document.write( "where and are the coordinates of points B and C. Put the equation into slope-intercept form (\r
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\n" ); document.write( "\n" ); document.write( "Step 2. Determine the slope of the line that contains the altitude segment, namely a line perpendicular to segment BC passing through A. First you need the slope of the line containing BC which you can obtain by inspection of the slope-intercept form of the equation of the line containing BC derived in Step 1.\r
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\n" ); document.write( "\n" ); document.write( "The slope of the line containing the altitude segment is the negative reciprocal of the slope of the line containing BC because:\r
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\n" ); document.write( "\n" ); document.write( "Step 3. Derive the equation of the line containing the altitude segment. Use the point-slope form of the equation of a line:\r
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\n" ); document.write( "\n" ); document.write( "Where are the coordinates of point A and is the slope number calculated in step 2. Put this equation in slope-intercept form as well.\r
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\n" ); document.write( "\n" ); document.write( "Step 4. Solve the system of equations derived in steps 1 and 3 to determine the point of intersection between the altitude and segment BC. Since both equations are in slope intercept form, you can simply equate the two right-hand sides and solve for , then substitute back into either equation to calculate . This is where this problem gets really ugly -- for example the -coordinate of the point of intersection is -- like a mud fence. But persevere and you will be rewarded in the end.\r
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\n" ); document.write( "\n" ); document.write( "Step 5. Use the distance formula:\r
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\n" ); document.write( "\n" ); document.write( "Where and are the coordinates of point A and the point of intersection calculated in step 4.\r
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\n" ); document.write( "\n" ); document.write( "d. Find the area of the traingle ABC.\r
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\n" ); document.write( "\n" ); document.write( "Use the distance formula to calculate the measure of segment BC:\r
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\n" ); document.write( "\n" ); document.write( "Where and are the coordinates of points B and C. Call this the measure of the base of the triangle.\r
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\n" ); document.write( "\n" ); document.write( "Use the area of a triangle formula:\r
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\n" ); document.write( "\n" ); document.write( "where is the measure of the base and is the measure of the altitude calculated in part c of the question.\r
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