document.write( "Question 69071This question is from textbook Algebra Stucture and Method Book 1
\n" ); document.write( ": A line passes through (-2,3), (2,5), and (6,k). Find k. \n" ); document.write( "
Algebra.Com's Answer #49151 by jim_thompson5910(35256)\"\" \"About 
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Start by finding the slope through the points (-2,3), (2,5). You can use the formula:
\n" ); document.write( "\"%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29\" which is simply a formal way to represent \"rise\" over \"run\". By plugging the points (-2,3), (2,5) into the formula it becomes
\n" ); document.write( "\"%285-3%29%2F%282-%28-2%29%29\"
\n" ); document.write( "which simplifies to
\n" ); document.write( "\"2%2F4=1%2F2\"
\n" ); document.write( "This number represents the slope of the line running through the points (-2,3), (2,5), and (6,k). To complete the equation of the line, we need to plug in one of those points. For instance, we can use the general form of the line equation: y=mx+b, where m is the slope and b is the y-intercept, and solve for b. So lets plug in the point (-2,3) in the equation along with the given slope:
\n" ); document.write( "\"y=mx%2Bb\" using (-2,3) and m=1/2
\n" ); document.write( "\"3=%281%2F2%29%28-2%29%2Bb\" solve for b
\n" ); document.write( "\"3=-1%2Bb\" isolate b
\n" ); document.write( "\"4=b\"
\n" ); document.write( "so the equation of the line is y=1/2x+4
\n" ); document.write( "Now all we need to do is plug in the point (6,k) to find k.
\n" ); document.write( "\"y=%281%2F2%29%286%29%2B4\"
\n" ); document.write( "\"y=3%2B4\"
\n" ); document.write( "\"y=7\"
\n" ); document.write( "so k=7 and the point is (6,7)
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