Answer:
y = (4/3)x - 1
Explanation:
"a y-intercept of -1" means that the line passes thru the point (0, -1).
Solving 4x-3y+9=0 for y is one way to determine the slope, m:
-3y = -4x - 9, and so:
y = (4/3)x + 3. The slope is 4/3.
Starting with the slope-intercept form of the equation of a str. line,
y = mx + b, we get:
-1 = (4/3)(0) + b. Then b = -1, and the equation is y = (4/3)x - 1.