Graph y = -2 + 1/4(x)
method 1: -2 is b, the y-intercept, so draw the first point at (0, -2). 1 over 4 is m, the slope, so from (0, -2) you go up 1 and over 4, since slope = rise over run. You arrive at (4, -1). Connect the two points with a line.
method 2: Use a table of values with easy points. Try x = 0, plug it in and you get y = -2, which you plot at (0, -2). Then try x = 4, simce when you plug it in the fraction 1/4 goes away. When x = 4, y = -2 + (1/4)(4) = -2 + 1 = -1, which you plot at (4, -1). Connect the two points with a line.
Graph the inequality y < -2 + (1/4)(x)
Pick a point in the blue region above the graph of y = -2 + (1/4)(x), such as (0, 0). Plug this point into the inequality y < -2 +(1/4)(x) and you get 0 < -2,which is false, so points in the blue region are not solutions.
Pick a point in the red region below the graph of y = -2 + (1/4)(x), such as (0, 0). Plug this point into the inequality y < -2 +(1/4)(x) and you get -3 < -2,which is true, so points in the red region are solutions.
To finish the graph, shade in the red region below the line.
Graph is a point on the number line: An equation in one variable.
Graph is a line or ray on the number line: An inequality in one variable.
Graph is a line on a plane: A linear equation in two variables.
Graph is an area or region on a plane: A linear inequality in two variables.
No comments:
Post a Comment