For each line, (a) find the slope and (b) sketch the graph. See Examples 6 and 7. y = 2x - 4
Verified step by step guidance
1
Identify the equation of the line, which is given in the slope-intercept form: \( y = mx + b \).
Recognize that in the equation \( y = 2x - 4 \), the coefficient of \( x \) is the slope \( m \).
Determine the slope \( m \) from the equation, which is \( 2 \).
To sketch the graph, start by plotting the y-intercept, which is the constant term \( -4 \) on the y-axis.
From the y-intercept, use the slope \( 2 \) (which means rise over run, \( \frac{2}{1} \)) to plot another point by moving up 2 units and 1 unit to the right, then draw the line through these points.
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above
Video duration:
5m
Play a video:
Was this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Slope
The slope of a line is a measure of its steepness and direction, calculated as the ratio of the vertical change (rise) to the horizontal change (run) between two points on the line. In the equation y = mx + b, 'm' represents the slope. For the line given by y = 2x - 4, the slope is 2, indicating that for every unit increase in x, y increases by 2 units.
The y-intercept of a line is the point where the line crosses the y-axis, which occurs when x = 0. In the equation y = mx + b, 'b' represents the y-intercept. For the equation y = 2x - 4, the y-intercept is -4, meaning the line crosses the y-axis at the point (0, -4). This point is crucial for sketching the graph.
Graphing a linear equation involves plotting points that satisfy the equation and connecting them to form a straight line. To graph y = 2x - 4, start by plotting the y-intercept at (0, -4) and then use the slope to find another point. From (0, -4), moving up 2 units and right 1 unit leads to the point (1, -2). Connecting these points gives the graph of the line.