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Old 06-February-2008, 04:15 PM
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dhd40 dhd40 is offline
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Quote:
Originally Posted by Tinaa View Post
I'm tutoring a friend in college algebra. She probably one of the most anal people (structured) I know, yet she cannot get basic college algebra. I've explained that one must follow the rules. She is learning graphing...basic Y= mx+b. She doesn't understand that b = y - intercept. Why doesn't y = y - intercept? m = slope but why doesn't x = x intercept? Arrrgh! HELP!
Should be very easy to explain if you agree on the definition of „intercept“:
y- intercept = value of y at x=0, which of course is y-intercept=m*0 +b = b
x-intercept = value of x at y=0, which is 0=m*x-intercept+b, or x-intercept = -b/m

Is that what you were asking for? Is it of any help?
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