Given the table of points below, determine the equation of the line that would pass through all the given points.
X Y
-1 2
0 0
1 -2
X Y
-1 2
0 0
1 -2
-
You essentially only need two of these points to set up the equation and this will work with either. I would use the first and second because the second is obviously easier.
Use the equation y=mx+b
Plugging in the middle point where y=0 and x=0, you get:
0=m(0)+b, which means b=0 when solving.
Next, you can use the top or bottom point. I'll use the top:
y=mx+b again where y=2, x=-1, and b=0 (from above)
so, 2=m(-1)+0
solving for m: m=-2
so, your final equation is y=-2x
hope that helps!
Use the equation y=mx+b
Plugging in the middle point where y=0 and x=0, you get:
0=m(0)+b, which means b=0 when solving.
Next, you can use the top or bottom point. I'll use the top:
y=mx+b again where y=2, x=-1, and b=0 (from above)
so, 2=m(-1)+0
solving for m: m=-2
so, your final equation is y=-2x
hope that helps!