Question

What is the equation of the line that passes throguh (0,-1) and (-1,2) (case 1)

Answer 1

y = -3x - 1

Explanation:

1) Find the slope of the line

`(y2-y1)/(x2-x1)`

`(2-(-1))/(-1-0)`

Slope is -3

2) Plug the slope into a y-intercept form.

y = mx +b

y = -3x + b

3) Find b (which is the y-intercept) by plugging in any coordinates for the x and y.

y = -3x + b

I would like to plug in (0, -1) into the equation.

(-1) = -3(0) + b

-1 = b

4) Plug in the b into the equation.

y = -3x +b

y = -3x -1