Answer:
y = -4x - 9
Step-by-step explanation:
The formula to calculate the slope of a line is
m = (y - y1) / (x - x1)
And the gradient form of the equation of a line is given as
y = mx + c
y and x represent coordinates. Points are represented as (x, y)
In this question, we are given the value of m to be
m = -4
y1 = -1
x1 = -2
Now we have
m = [y - (-1)] / [x - (-2)]
-4 = (y + 1) / (x + 2)
We then cross multiply to get
y + 1 = -4(x + 2)
y + 1 = -4x + (-8)
y + 1 = -4x - 8
y = -4x - 8 - 1
y = -4x - 9
Therefore the equation of the equation of a line with slope -4 and containing the point (-2,-1) is
y = -4x - 9
