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You can put this solution on YOUR website!
\n" ); document.write( "I have seen countless examples of where a student blindly plugs numbers into the textbook formula for finding the slope of a line through two points and gets the wrong answer by plugging the wrong numbers in the wrong places.
\n" ); document.write( "Plugging numbers into a formula doesn't help you learn anything. I always encourage students to use an informal common sense method for finding a slope.
\n" ); document.write( "Somewhat informally, slope is defined as \"rise over run\". Even more informally, the slope tells you how much you move up or down as you move 1 unit to the right.
\n" ); document.write( "So to find the slope of the line through the two given points, first make sure you are moving from left to right; then determine how far you are moving right (run) and how far you are moving up or down (rise); then find the ratio of rise to run.
\n" ); document.write( "The second given point is farther to the left (x=1 is to the left of x=10), so start at (1,9) and move to (10,8). The run (change in x) is from 1 to 10, a difference of 9; the rise (change in y) is from 9 to 8, a difference of -1; so the slope is rise/run = -1/9.
\n" ); document.write( "You will understand math better, and enjoy it more, if you use methods that let you see what you are doing, instead of relying on magic formulas.
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\n" ); document.write( "It's beyond my understanding why anyone who considers themselves a \"teacher\" of mathematics would say it is stupid for a student to understand mathematics, instead advocating for teaching the student to do mathematics by plugging numbers into formulas....
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