- Forum
- General C++ Programming
- Solving quadratic equation in system
Solving quadratic equation in system
I need to find a parabola's equation given 3 points. How can I solve with a program a 2nd degree system with 3 equations? Is there a special library that I can use?
For a parabola, I don't think you need a special library, or even a program. A parabola is easy enough to solve with pencil, paper, and a calculator.
A parabola takes the general form y = a x^2 + b x + c
If one of the points you have happens to be at x = 0, you can solve for c immediately. That leaves two equations in two unknowns, which you can solve by substitution.
On the other hand, if you are not given the coordinate at x = 0, it becomes slightly harder. You would form three equations in three unknowns. It would involve one more step, but still pretty simple.
A parabola takes the general form y = a x^2 + b x + c
If one of the points you have happens to be at x = 0, you can solve for c immediately. That leaves two equations in two unknowns, which you can solve by substitution.
On the other hand, if you are not given the coordinate at x = 0, it becomes slightly harder. You would form three equations in three unknowns. It would involve one more step, but still pretty simple.
Topic archived. No new replies allowed.