Question

What is the slope-intercept equation of the line below?

Answer 1

D

Explanation:

We will use the 2 coordinates marked on the graph as the reference.

The coordinates are:

A(4,-2)

B(0,3)

We know that the standard form for equation of line is:

y = mx+c

where m is the slope of the equation

and c is the y-intercept.

Very clearly, the y-intercept is where the line intercepts the y line.

and in this case, y-intercept = c = 3.

Now we know that the equation of line is now

y = mx + 3

To find m, the slope, we can use the 2 above coordinates.

slope of line =
`(y1-y2)/(x1-x2) \\=(-2-3)/(4-0) \\=(-5)/(4) \\=-(5)/(4)`

(Note: There is a 2nd way to find the slope in this case, let me know if you are interested to find out.)

Equation of line:
`y=-(5)/(4) x+3`

Therefore the answer is D.