420 likes | 590 Views
Quadratics. This is the “parent”. y = x 2. Flips up because positive value. Doesn’t move left or right on x axis. Stays at 0. Doesn’t move up or down y axis. Stays at 0. Makes parabola wider. y = 1/2 x 2. Flips up because negative value. Doesn’t move left or right. Stays at 0.
E N D
This is the “parent”. y = x 2 Flips up because positive value Doesn’t move left or right on x axis. Stays at 0 Doesn’t move up or down y axis. Stays at 0
Makes parabola wider y = 1/2 x2 Flips up because negative value Doesn’t move left or right. Stays at 0 Doesn’t move up or down. Stays at 0
Makes parabola skinnier y = -4x2 + 2 Flips down because negative value Doesn’t move left or right. Stays at 0 Moves up 2 on y axis
Makes parabola wider y = 1/2 (x+3)2 Flips up because negative value Moves left 3 on x axis Doesn’t move up or down. Stays at 0
y = (x – 4)2 + 5 Flips up because positive value Moves right 4 on x axis Moves up 5 on y axis
y = -(x + 2)2 - 5 Flips down because negative value Moves left 2 on x axis Moves down 5 on y axis
Moves parent right 4 and up 5. This is the NEW vertex. x intercept: y intercept: vertex: D: R: none (0,21) (4,5) { y : y > 5} Quadratic Family
HOW DO YOU FIND THE X INTERCEPTS? Set y = 0 0 = - 3(x – 4)2 + 9 Minus 9 from both sides. -9 = - 3(x – 4)2 Divide by -3 3 = (x – 4)2 1.73 = x – 4 -1.73 = x - 4 Square Root both sides Solve. (5.73, 0) and (2.27, 0)
HOW DO YOU FIND THE X INTERCEPTS? Factor OR Quadratic Formula Set y = 0
HOW DO YOU FIND THE VERTEX? This gives you the X COORDINATE of the vertex. To find the y, substitute this x into the original and evaluate. -b OR You Could Use the Midpoint of the x intercepts. 2a
HOW DO YOU FIND THE VERTEX? Find the midpoint of the x intercepts. Then substitute that x into the original to find it’s y coordinate.
HOW DO YOU FIND THE X INTERCEPTS? Set each factor equal to 0 and solve. (Take the opposite of them.) 6th hour ends. They need rest of this and FF1 (-8,0) and (2,0)
x intercept: y intercept: vertex: D: R: (-2/3, 0) (2/5, 0) (0,-4) (-2/15, -4.27) { y : y > -4.27} Quadratic Family
x intercept: y intercept: vertex: D: R: (4, 0) (3, 0) (0,12) (3.5, -.25 ) { y : y > -.25} Quadratic Family
Because there are NO x intercepts YOU MUST USE –b/2a to find the VERTEX!!! x intercept: y intercept: vertex: D: R: NONE (0,1) (-3, -8) { y : y >-8} Quadratic Family