Saturday, July 27, 2013
Yesterday we learned a bit about slope and how horizontal lines will always have a slope of zero because if you divide zero by any number it is still zero. This brings us to vertical lines, these lines have a change in x of zero, because we can't divide by zero the slope of any vertical line is undefined. Given two points (x1, y1) (x2,y2) we can then find the slope using this equation where "m" stands for slope, m=(y1-y2)/(x1-x2). So how do we find the graph or visual representation of a line from this information? We use the slope of a line and a point on the line, we can also represent a line using slope-intercept form. This uses the slope and the y intercept to represent a line or y=mx+b where again m is slope and b is the value of y at the y intercept. We can also use point-slope form y-y1=m(x-x1) where (x1, y1) is any point on the line. If we solve for y we can convert point-slope form to slope-intercept form.