Final answer:
The two possible values of y are -20 and 12.
Step-by-step explanation:
The distance between two points on a coordinate plane can be found using the distance formula:
d = sqrt((x2 - x1)^2 + (y2 - y1)^2)
In this case, the coordinates of point P are (3, y) and the coordinates of point Q are (1, -4).
We are given that the distance between P and Q is 29 units.
Plugging in these values into the distance formula, we get:
29 = sqrt((1 - 3)^2 + (-4 - y)^2)
Simplifying, we get:
841 = 4 + y^2 + 8y
Rearranging and solving the quadratic equation, we find two possible values of y: -20 and 12.