Question

(Help) Here's a graph of a linear function. Write the equation that describes that function. (Zoom in if blurry)

Answer 1

Answer:

y = 0.5x -3

Step-by-step explanation:

Slope-intercept form is y=mx+b. The y-intercept (where it crosses the y axis, represented by b) is -3. The rise over run is 1/2, which is the slope.

Answer 2

Answer: y = x/2 - 3

Step-by-step explanation:

The equation of a straight line can be represented in the slope-intercept form, y = mx + c

Where c = intercept

Slope, m =change in value of y on the vertical axis / change in value of x on the horizontal axis

change in the value of y = y2 - y1

Change in value of x = x2 -x1

y2 = final value of y

y 1 = initial value of y

x2 = final value of x

x1 = initial value of x

From the graph,

y2 = - 1

y1 = - 2

x2 = 4

x1 = 2

Slope,m = (- 1 - - 2)/(4 - 2) = 1/2

To determine the intercept, we would substitute x = 4, y = - 1 and m= 1/2 into

y = mx + c. It becomes

- 1 = 1/2 × 4 + c

- 1 = 2 + c

c = - 1 - 2 = - 3

The equation becomes

y = x/2 - 3