graph the linear equation by solving for y first
-2x+5y=-15
+2x +2x
5y = 2x - 15
/5 /5 /5
y=2/5x -3
1st oredered pairs of y=2/5x-3 is (0,-3)
graph the linear equation by solving for y first
-2x+5y=-15
+2x +2x
5y = 2x - 15
/5 /5 /5
y=2/5x -3
1st oredered pairs of y=2/5x-3 is (0,-3)
You worked everything out perfectly. So you have the following linear equation:
y = (2/5)x - 3
The first ordered pair you found is (0, -3), which means that when x = 0 then y = -3.
So for the next ordered pair, pick an x and plug it into the equation to solve for y.
For simplicity, let's solve for y when x = -5 and when x = 5:
x = -5
y = (2/5)(-5) - 3
y = -2 - 3
y = -5
thus, this ordered pair is (-5, -5)
x = 5
y = (2/5)(5) - 3
y = 2 - 3
y = -1
thus, this ordered pair is (5, -1)
In the formula y=mx +b, m = the slope of the line. This is how the points on the line are plotted. If you've found the first point is (0, -3) then since the slope is 2/5 2 = the movement on the y axis, and 5 = the movement on the x axis. You can either move have the next point be up 2 and over 5 to the right from (0, -3) or down 2 and back 5 from (0, -3). Therefore 2 other points that should work are (5, -1) and (-5, -5). Plug both into your equation of y = 2/5x - 3 and you will see that both points fit into the line.
Another option is to plug any number in for x OR y in order to find new points. An example would be to plug 5 in for x and solve for y: y = 2/5 (5) - 3. y= 2 - 3 and y would then equal -1.
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