How do you graph #-3y=-2x-6# by plotting points?
1 Answer
Feb 17, 2016
see explanation
Explanation:
To sketch the equation of a straight line only requires 2 points , although 3 is better as it assists with alignment.
When the line crosses the x-axis , the y-coord will be zero. By letting y= 0 and substituting into the equation , obtains the corresponding x-coord.
y = 0 gives - 2x - 6 = 0 → x = - 3 → ( - 3 , 0 ) is 1st point.
Similarly when the line crosses the y-axis the x-coord will be zero.
x = 0 gives - 3y = -6 → y = 2 → ( 0 , 2 ) is 2nd point.
To find a 3rd point , choose any value for x , say x = 3
x = 3 gives - 3y = -6 - 6 = -12 → y = 4 → (3 , 4 ) is a 3rd point.
Now plot the points (-3 , 0 ) , (0 , 2 ) and (3 . 4 ) and draw a straight line through them.
here is a sketch of the line
graph{2/3x+2 [-10, 10, -5, 5]}
