[tex]\begin{gathered} v_{fy}=?,\text{ }v_{oy}=0\text{ m/s} \\ g=9.81m/s^2 \\ h=3\text{m} \\ v^2_{fy}=v^2_{oy}+2gh \\ v^2_{fy}=2gh \\ v_{fy}=\sqrt{2gh} \\ v_{fy}=\sqrt[]{2(9.81m/s^2)(3\text{ m})} \\ v_{fy}=7.67\text{ m/s} \\ v_x=1.75\text{ m/s} \\ v=\sqrt{v^2_x+v^2_{fy}} \\ v=\sqrt[]{(1.75\text{ m/s})^2+(7.67\text{ m/s})^2} \\ v=7.87\text{ m/s} \\ \text{The spe}ed\text{ just before she enters the water is }7.87\text{ m/s} \end{gathered}[/tex]
