First you have find the slope (a) in order to find the value of the y intercept (b).
To compute the slope, you simply have to find the difference of y coordinates and divide them by the difference of x coordinates:
a = (y2-y1)/(x2-x1)
a = (7-3)/(-2–0)
a = 4/-2
a = -2
To compute the y intercept denoted by b, we substitute the value of a with -2 in the formula and choose any point (x,y) and substitute their values in the formula as well. Like so:
I choose point A:
3 = (-2)(0) + b
3 = b
Where is the data/info at
So you want height to be 0 so you plug zero into the height and solve from there. You subtract 192 from both sides to get -192=-16tsquared. Then you would divide by -16 and end up with 12 = t^2. Then you find the square root of 12 and get t = 3.464 seconds.