# Using the points from the graph (-1,0),(-2,2) find the equation of the line in slope intercept form.

sciencesolve | Teacher | (Level 3) Educator Emeritus

Posted on

You should remember what is the slope intercept form such that:

`y = mx + b`

m represents the slope of the line

b represents the y intercept

You need to write the equation such that:

`y - y_1 = m(x - x_1)`

`m = (y_2 - y_1)/(x_2 - x_1)`

Substituting the given coordinates for `x_1,y_1,x_2,y_2`  yields:

`y - 0 = (2-0)/(-2+1)(x+1)`

`y = -2(x+1) => y = -2x - 2`

Hence, evaluating the slope intercept form of the equation under the given conditions yields `y = -2x - 2` .

Sources:

dlccanada | High School Teacher | (Level 1) eNoter

Posted on

you know the equation of line in slope(m) and y-intercept(b) form is

y=mx+b ,

Now you have to find the slope from the given two points using the slope formula

=(2-0)/(-2+1)=-2

therefore the equation becomes

y=-2x+b, now you have to findout b,to findout b, sub any of the given two coordinates and solve for b. say you sub (-1,0)

0=-2(-1)+b

b=-2

the equation of the line in y=intercept  and slope form will

y=-2x-2 where , slope=m=-2 and y-intercept=b=2