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-4x - 16x= -12

use the y intercept and slope to sketch the graph of the equation

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Joshua S. | Math and English Tutor: 8th Grade and BelowMath and English Tutor: 8th Grade and Be...
-4 - 16 = -20
Jeffrey P. | Life Science and Math Tutor with over 10 years experienceLife Science and Math Tutor with over 10...
4.3 4.3 (7 lesson ratings) (7)
Assuming there are no typos: -4x-16x = -12
So... -20x = -12
Divide both sides by -20 to isolate your variable
and x = -12/-20 or 3/5 =x
lines generally take the form of y= mx + b  (where m represents the slope and b the y intercept)
in the equation x = 3/5 no matter what y equals x will be the same.
So what you get is a vertical line at 3/5.  This line will not have a y-intercept as it never crosses that axis.  It's slope will also be undefined.
Felice R. | Need Help in Math and Science - Engineer willing to helpNeed Help in Math and Science - Engineer...
4.0 4.0 (1 lesson ratings) (1)
I think that one of your x terms needs to be y.
lets assume your equation was -4y-16x = -12
we know that the slope intercept formula is y = mx + b
so we need to get your equation into the same format
-4y -16x + 16x = -12 + 16x
-4y = 16x -12
divide each side by -4
-4y/(-4) = (16x - 12)/(-4)
which gives you (the slope intercept equation for the line)
y = -4x + 3
using this line and slope intercept formula you know that the slope, m =-4 and your y-intercept , b = 3
your y-intercept is the value of y on your line when x = 0 so you have one point (0,3)
You need another point to draw/graph the line
Now another way of looking at your slope is knowing that it is equal to the change of y divided by the change in x
m = (y1-y2)/(x1-x2)
since your slope is -4 which can be written as -4 = -4/1  using the concept above you could take your point (0,3) and know that if you moved y 4 points down on the graph and x one point to the right you would get the next point (1,-1). You can then graph your line using those two points
OR you could substitute in different values for x into the slope intercept equation for the line and determine a new y
y = -4x + 3
using x = 1, y = -4(1) + 3 = -4 + 3 = -1   point (1,-1)
Which is the same as the value of the point you would get from moving along the graph.  I hope this helps