Free · Worked example · 14 problems · Answer key · US Letter
How to do it
Complete the square to write y = a(x − h)² + k. The vertex is (h, k).
y=x2+2x−6→y=(x+1)2−7 y=(x2+2x+1)−7add (2 ÷ 2)² = 1 inside and subtract it outside y=(x+1)2−7write the square; the vertex is (−1, −7) Example problems
- y=−x2−2x+10→
- y=x2+8x+13→
- y=x2+10x+35→
- y=x2+14x+55→
Quadratic and polynomial functions
- Vertex form of a quadratic
- Finding the vertex from standard form
- The discriminant
- Quadratic equations with complex roots
- Polynomial long division
- Synthetic division
- The remainder theorem
- The factor theorem
- The rational root theorem