I read Zen's question wrong, so I'll repost. Quadratic EQUATION,not formula, right?

1. Parabolic motion, (projectile motion) is indeed the best application. Life is rarely a straight line. By the time students take Algebra, they are expected to be able to solve and graph these equations. Life is rarely a straight line. Analyzing graphs is a part of logical thinking and problem solving. No one expects little kids to do this while they play in the yard! On the other hand, my physics students solve these projectile motion problems using sin, cos and tan, and then using the acceleration due to gravity. I might add that they also hate these problems, so I include one on every test.lol

2. It's not Trig. They learn these in Algebra I in 8th grade. Three years before they step into my Trig class. The reason so many people don't know them is simply because they don't remember them. You've all probably done them.

3. An example that isn't a parabola. Say you have a garden and you want it to be 2 ft longer than it is wide. You also want it to be 24 square feet. To find the dimensions you should plant, you would take the length times the width for the area. x(x - 2) = 24. You would then set up the equation x^2 - 2x -24 = 0. Factor it: (x-6)(x + 4) = 0. x would then be either 6 or -4. Since you can't have a negative length, the length of the garden is 6 and the width (6-2) is 4.

If she needs any help, just message me. Now if she wanted to know about the quadratic FORMULA, let me know. That's how I first interpreted it.