Using the Slope-Intercept FormulaDate: 9/27/95 at 22:30:28 From: Andy Plotkin Subject: Algebra II Honors High School Is y = 11x + 6 and y - 7 = 11(x - 3) the same thing? "Has x- intercept of 5 and slope of -2/3" How would I write an equation for the line described? Thank You, Wendy Plotkin Date: 9/27/95 at 22:45:28 From: Doctor Andrew Subject: Re: Algebra II Honors High School If you can find two different points (x,y) that satisfy both equations you've got the same line, since two points uniquely define a line. You could also show that they are algebraically equivalent by solving each one for zero (0 = ab + by + c), setting the non-zero sides equal to each other and seeing if you can get 0 = 0. >"Has x- intercept of 5 and slope of -2/3" How would I >write an equation for the line described? The slope/intercept form of the equation for a line is: y = mx + b where m is the slope and b is a Y-intercept. However, you don't know the y-intercept, you know the x- intercept. The x-intercept is the value of x such that y = 0. So if you plug in the slope into m, the x-intercept value into x, and let y = 0, you can solve for b, the y-intercept. Hope this helps. Good luck! -Doctor Andrew, The Geometry Forum |
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