1. 10.7 Parametric Equations
parametric equations: a pair of equations, one for x and one for y, relating both to a third variable t.

2. Example 1:
Eliminate the parameter for the curve below:

3. Example 2:
Eliminate the parameter for the curve below:

4. Projectile Motion
When a projectile is in two dimensional motion, the parametric equations for its motion are defined as follows:

5. Velocity Vector Components
If v is the velocity vector with angle θ, then the horizontal and vertical components can be found by the following equations:

6. Example 3:
Jack throws a baseball from 6 ft above the ground with an initial speed of 20 ft/sec at an angle of 35°. How far does the ball travel?

7. Example 3:
To find when the ball hits the ground, we set the second equation equal to zero and solve

8. What is an alternative way of solving for time in this situation???
Example 3:
Since the problem only makes sense if we time starting from t=0 we’ll use the second value in our horizontal distance equation.
What is an alternative way of solving for time in this situation???

9. Example 3: s

10. 10.7 HW Assignment
Pg. 694: #s 8-16 evens (eliminate the parameter), 54 (a-d only), 56 (a-d only)