posted by Esther on .
Find an equation of the line containing the given pair of points (-1,-6) and (-4,-8). The equation of the line in slope intercept form is y=?
This is the most fundamental of questions in the topic of linear functions.
You must learn and practise how to do this.
1. find the slope
slope = (-8+6)/(-4+1) = -2/-3 = 2/3
2. let the equation be
y = (2/3)x + b
3. sub in one of the given points, I will use (-1,-6)
-6 = (2/3)(-1) + b
-6 = -2/3 + b
-16/3 = b
4. rewrite the equation using the found value of b
y = (2/3)x - 16/3
I also suggest testing your equation with the point that was NOT used in finding b