To determine the correct system of equations shown on the graph,
- Choose any two points on the line.
- Determine the x and y coordinates of all points
- Determine the slope of the line
- Determine the y-intercept of the line.
- Plug the slope and the y-intercept in the slope intercept form.
Determining the equation of the blue line
Choosing any two points on the blue line:
- Chosen points on blue line: (0, 5) and (3, 4)
Determining the coordinates of the two points:
- y-coordinate of second point = y₂ = 4
- y-coordinate of first point = y₁ = 5
- x-coordinate of second point = x₂ = 3
- x-coordinate of first point = x₁ = 0
Determining the slope of the line:
Substitute the coordinates into the slope formula:
Simplify the expression as needed:
Therefore, the slope of the blue line is -1/3.
Determining the y-intercept of the line:
The point of the blue line that is intersecting the y-axis is (0, 5).
Therefore, the y-intercept of the blue line is 5.
Plug the slope and the y-intercept in the slope intercept form.
Slope intercept form: y = mx + b
[Where "m" is the slope and "b" is the y-intercept]
⇒
⇒
⇒
Therefore, the equation of the blue line is y = -1/3x + 5
Determining the equation of the red line:
Choosing any two points on the red line:
- Chosen points on red line: (0, -2) and (1, 0)
Determining the coordinates of the two points:
- y-coordinate of second point = y₂ = 0
- y-coordinate of first point = y₁ = -2
- x-coordinate of second point = x₂ = 1
- x-coordinate of first point = x₁ = 0
Determining the slope of the line:
Substitute the coordinates into the slope formula:
Simplify the expression as needed:
Therefore, the slope of the red line is 2.
Determining the y-intercept of the line:
The point of the red line that is intersecting the y-axis is (0, -2).
Therefore, the y-intercept of the red line is -2.
Plug the slope and the y-intercept in the slope intercept form.
Slope intercept form: y = mx + b
[Where "m" is the slope and "b" is the y-intercept]
⇒
⇒
⇒
Therefore, the equation of the red line is y = 2x - 2
Final answer:
y = 2x - 2 and y = -1/3x + 5 ======> Option A