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You can put this solution on YOUR website!
\n" ); document.write( "I encourage students to practice being able to solve problems like this using your UNDERSTANDING of the problem, without the formal algebra.
\n" ); document.write( "As you will see (comparing my solution method with those shown in the other responses you have gotten), finding the answer is much easier this way (if you understand it!) than with the formal algebra.
\n" ); document.write( "(1) The line passes through the points (-4,k) and (-1,2k). So in moving 3 to the right, from -4 to -1, the y value changes by k, from k to 2k.
\n" ); document.write( "(2) We want the value of k that makes the y-intercept -7.
\n" ); document.write( "(3) The y-intercept is when x=0, which is 1 unit to the right of (-1,2k).
\n" ); document.write( "(4) Since this is a straight line, changing the y value by k when the x value changes by 3 means changing the y value by k/3 when the value of x changes by 1.
\n" ); document.write( "(5) So the y-intercept is at (0,2k+k/3), or (0,7k/3).
\n" ); document.write( "(6) Since we want the y-intercept to be (0,-7),
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\n" ); document.write( "ANSWER: k = -3
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