Let us assume that when both boats reach the edge of the cliff, their velocities are horizontal, since otherwise is not specified in the problem. This means, it will take them the same time to land 5 below the cliff. This time is determined by the equation
`h=(g*t^2)/2` , where h is the height h = 5m, g is the acceleration of the free fall g = 9.8 m/s^2, and t is the time. From here,
`t = sqrt((2h)/g) =1.02 s` .
The horizontal distance between the point where the first boat lands and the cliff is
`d_1= v_1 * t` , where `v_1` is the speed of the first boat, 15 m/s. Plugging in the time it takes the boat to reach the bottom, we get
`d_1 = 15 * 1.02 =15.3 m`
Similarly, we can find the distance between the point where the second boat lands and the cliff:
`d_2 = v_2*t = 26 * 1.02 =26.5 m`
So the distance between the boats when they land will be
`d_2 - d_1 = 26.5 - 15.3 = 11.2 m`
The boats will be 11.2 meters apart when they land.