Quadratic Function Word Problems

Both Taisha and Elle are divers on the swim team of their school. Taisha usually jumps from a $10$ meter board and Elle likes jumping from a $5$ meter board the best. They claim they take the same amount of time to enter the water, jumping from their respective board. Their friend Luca is not convinced and wants to see it for herself. Taisha and Elle take turns jumping from each of their board. The following equations models their height above the pool at time t in seconds. $$\text{Taisha}: y = -4.2t^2+4t+10 \\ \text{Elle}: y=-2t^2+2t+ 5$$