The following table of values represents a line.
x | y
-10 | 19
0 | -1
10 | -21
50 | -101
Identify the equation of the line. Write the equation in slope-intercept form.
My answer: −2x+(−1)
The answer came out incorrect, and the correct answer was −2x+−1, did i make an error?
Yes, it seems like you made a small error in your answer. The correct answer should be −2x + (−1), as you mentioned. However, it is more common to write it as −2x − 1 in slope-intercept form.
To find the equation of a line in slope-intercept form, you need two pieces of information: the slope (m) and the y-intercept (b).
To find the slope, you can use the formula:
m = (change in y) / (change in x)
From the given table, we can calculate the change in y and the change in x for two points. Let's choose the points (-10, 19) and (0, -1):
change in y = -1 - 19 = -20
change in x = 0 - (-10) = 10
m = (-20) / 10 = -2
So the slope (m) of the line is -2.
Next, we need to find the y-intercept (b). To do this, we can use any of the given points. Let's use the point (0, -1):
y = mx + b
-1 = -2(0) + b
-1 = b
Therefore, the y-intercept (b) is -1.
Now that we have the slope (m = -2) and the y-intercept (b = -1), we can write the equation in slope-intercept form:
y = mx + b
y = -2x - 1
So, the correct equation of the line in slope-intercept form is y = -2x - 1.