Answer is A. y = 4x - 3
Graph the line using the slope and y-intercept, or two points.
Slope: 2/
5
y-intercept: (
0
,
−
1
)
x
y
0 −
1
5/
2 0
Step-by-step explanation:
How do you graph y=4x-3?
In graphing an equation, a very valuable graphing technique is the ability to recognize the kind of graph that a certain type of equation produces.
Any equation that is of the form y = mx + b is in the "slope-intercept" form for the equation of a straight line, where x and y are variables, where “m” is a real number representing the slope of a line, and where “b” is a real number representing the y-intercept of a line , i.e., the y-coordinate of the point of intersection between a straight-line graph and the y-axis.
Since the given equation y = 4x ‒ 3 is in the slope-intercept form, where m = 4 and b = ‒3, then it’s a linear equation and its graph is a straight line. Also, looking at the given equation, we know that the independent variable x can take on any real number as a replacement.
Now that we know that the graph of the given equation is a straight line and that there are no restrictions on the variable x, we need to determine and then draw the straight-line graph on a Cartesian (rectangular) coordinate system with the y-axis as the vertical axis and the x-axis as the horizontal axis. We know that two points determine a straight line; So, all we need to do is find the point where the straight-line graph of the given equation y = 4x ‒ 3 intersects the x-axis, i.e., the point of the x-intercept, and find the point where the straight-line graph of y = 4x ‒3 intersects the y-axis, i.e., the point of the y-intercept. Also, it would be a good idea to plot a third point as a check.
(1.) Determining the point of the x-intercept:
For any point on the x-axis, the y-coordinate is zero; therefore, in our given equation, let y = 0 and solve for x as follows:
y = 4x ‒3
0 = 4x ‒3
0 + 3 = 4x ‒3 + 3
(1/4)(4x) = (1/4)(3)
x = 3/4
Therefore, the x-intercept is x = 3/4, and the graph of the given equation y = 4x ‒3 intersects the x-axis at the point (3/4, 0).
(2.) Determining the point of the y-intercept:
To get the y-intercept, we can simply select it from the given equation y = 4x ‒3 which is already in slope-intercept form (y = mx + b), i.e., y = 4x ‒3 or y = 4x + (‒3); therefore, the y-intercept of the straight-line graph of the given equation is y = b = ‒3, which is the y-coordinate of the point of intersection between the straight-line graph of the given equation and the y-axis. Also, for any point on the y-axis, the x-coordinate is zero; therefore, the straight-line graph of the given equation intersects the y-axis at the point (0, ‒3).
(3.) Check Point
In generating a third point as a check point, choose a convenient value for x so that the corresponding value for the dependent variable y is nice and even. Let x = 2, then:
y = 4x ‒3
= 4(2)‒ 3
= 8 ‒ 3
y = 5
Consequently, the third point (check point) on the straight-line graph of the given equation is (2, 5).
(4.) Plot the points
Now, create the straight-line graph of the given equation by plotting the three points: (3/4, 0), (0, ‒3), and (2, 5) on a Cartesian (rectangular) coordinate system, and then use a straight edge to draw the straight line through all three plotted points. Draw the line past the two outer points and then draw an arrowhead at each “end” of the line to show that the line goes on indefinitely in both directions. NOTE: If the third point (2, 5)(the check point) is not on the drawn line, then go back and look for an error. The error was either made in finding the x- and y-intercepts, or the error was made in generating the coordinates of the check point, or both. When the error is found, make the appropriate correction(s), and then redraw the graph (straight line) of the given equation.
These are four steps that you can use to graph the given equation y = 4x ‒3 or any equation that is in the slope-intercept form for the equation of a straight line: y = mx + b.
