1.9k views
3 votes
Find the slope of each line.

1 Answer

7 votes

Can you please provide the lines we need to work on?

Upload ONLY one image, please

Recall that in order to find the equation of a line, we need at least TWO points on the plane. So we are going to use the two points that are marked with blue dots:

the oe more towards the left and down is the point (-3, -3) and the point to the right of the y-axis is (1, -1).

So we use them in the formula for the slope:

slope = (y2 - y1) / (x2 - x1)

in our case:

slope = (-3 - (-1)) / (-3 -1) = (-3+1) / (-4) = -2 / (-4) = 1/2

Then 1/2 is our slope.

So we use this slope "m" = 1/2 in the general slope-intercept form of a line:

y = m x + b

and replace m with "1/2":

y = (1/2) x + b

all we need now is the value of "b" (called the y-intercept), and for that we use either point in the equation above, for example point (1, -1), to determine its value:

-1 = (1/2) (1) + b

-1 = (1/2) + b

subtract 1/2 from both sides to isolate "b"

- 1 - 1/2 = b

then b = - 3/2

and now we can write the equation of this line in slope intercept formas:

y = (1/2) x - 3/2

Find the slope of each line.-example-1
User Kamilla
by
7.9k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories