Question

Line JK passes through points J(-4,-5) and K(-6,3). If the equation of the line is written in slope-intercept form, y-mx+b, what is the value of b?

Answer 1

Explanation:

A) -21

Answer 2

`y=mx+b \\ \\ (x,y)=(-4,-5) \hbox{ and } (x,y)=(-6,3) \\ \Downarrow \\ -5=-4m+b \ \ \ \ \ \ \ \ \ \ \ \ \ \ | * (-3) \\ 3=-6m+b \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |* 2 \\ \\ 15=12m-3b \\ \underline{6=-12m+2b} \\ 21=-b \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |* (-1) \\ \boxed{b=-21}`

The value of b is -21.