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?

The value of "b" is the y-intercept.

In order to figure out slope-intercept form you need 1 coordinate and the slope.
1) Find the slope, using the 2-point slope formula: "m= y2-y1 / x2-x1".
   ex. m= -5 - 3 / -4 - -6   (simplify)--->   m= -4

2) Fill in the blanks for point-slope formula: "y - y1 = m (x - x1)"
(choose one coordinate, it doesn't matter which one)
   ex. y - -5 = -4 (x - -4)

3) Then use basic algebra to simplify.