Expert: Richard J. Raridon - 1/12/2010

Question
"Write each equation in slope-intercept form.
* y + 3 = -3(x – 6)

Write each equation in standard form using only integers
* y= 1/3 x+5

Find the equation of the line through each given pair of points.
Write the answer in standard form using only integers.
* (2, 5) (3, 9)

Find the equation of each line in the form y = mx + b if
possible.
* The line through the origin that is perpendicular to y = 2/3 x

* The line through (3, 1) that is parallel to the line through (-3, -2) and (0, 0)"

Answer
y+3 = -3x+18, y = -3x+15
First of all you need to write it y = (1/3)x +5 to avoid making it look like having 3x in the denominator.  So just multiply each term by 3 to get 3y = x+15, or 3y-x = 15
For the points (2,5) and (3,9) you have 5 = 2m +b and 9 = 3m +b so m=4, b=-3 and the equation is
y = 4x-3
the line through the origin that is perpendicular to y = (2/3)x is y = (-3/2)x
the line through (-3,-2) and (0,0) is y = (2/3)x. the parallel line through (3,1) is y = (2/3)x-1