Answer:
a) Use the two points to compute the slope, then put that and one of the points into the point-slope form
b) Eliminate parentheses and solve for y to get the equation in slope-intercept form
c) From slope-intercept form, subtract the x-term, then multiply by a common denominator of there are any fractions. Multiply by -1 if necessary to make the x-coefficient positive.
Step-by-step explanation:
a) The slope (m) is computed from two points by ...
... m = (y2 -y1)/(x2 -x1)
That value and one of the points goes into the point-slope form ...
... y -y1 = m(x -x1)
b) Putting the above equation into slope-intercept form is a matter of consolidating all of the constants.
... y = mx +(-m·x1 +y1)
c) Rearranging to standard form puts the x- and y-terms on the same side of the equal sign, preferably with mutually prime integer coefficients. This may require that the equation be multiplied by an appropriate number. The x-coefficient should be positive.
<u>Example:</u>
y -3 = 1/2(x +7) . . . . . . line with slope 1/2 through (-7, 3)
-1/2x + y = 7/2 + 3
x -2y = -13 . . . . . . . . . multiply by -2 to get standard form
