Quadratic Review Aug. 28 and 29
Bell Ringer: Find the roots of the following: 1. 2. Use the Quadratic Formula: 2 𝑥 2 −4𝑥−3=0 (round two places after the decimal) 3. Use factoring: 𝑥 2 +0𝑥−1=0
Axis of Symmetry The axis of symmetry is where the graph is cut in half and symmetrical on both sides. Ex: x=2
Axis of Symmetry To find the AoS given an equation, y=𝑎 𝑥 2 +𝑏𝑥+𝑐, plug into 𝑥= −𝑏 2𝑎 Ex: 4 𝑥 2 +5𝑥−15 Ex: 3 𝑥 2 −6𝑥+2
Vertex The vertex is the point at the top, or the bottom, of the parabola. In order to find the vertex, you must 1. Find the axis of symmetry (𝑥=− 𝑏 2𝑎 ) 2. Plug your x into the original equation 3. Solve for y 4. Write as an ordered pair
Vertex 𝑧 2 −6𝑧+6=0 1. Axis of Symmetry z= − −6 2(1) = 6 2 =3 2. Plug into equation 𝑦= 3 2 −6 3 +6 3. Solve for y 𝑦=9−18+6=−3 4. Write as an ordered pair (3, -3)
Vertex 5 𝑥 2 −2𝑥−3
Vertex 2𝑥 2 +8𝑥+6