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Quadratic equations. Graphing and Solving with x 2. The typical form of a y = x 2 graph:. Quadratic equations Quick Exercise:. Graph the following on the same axes: y = x 2 y = x 2 + 2 y = x 2 - 2x. The form of a y = x 2 + b x + c graph:. General Form of Quadratics.
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Quadratic equations Graphing and Solving with x2
Quadratic equationsQuick Exercise: Graph the following on the same axes: y = x2 y = x2 + 2 y = x2 - 2x
General Form of Quadratics The general form is either: • y = ax2 + bx + c Or • ax2 + bx + c = 0
General Form of Quadratics The general form is either: • y = ax2 + bx + c used for graphing Or • ax2 + bx + c = 0
General Form of Quadratics The general form is either: • y = ax2 + bx + c used for graphing Or • ax2 + bx + c = 0 when solving for x For now, we will stick to when a = 1
Quadratics • The equation for such a modified parabola is called a quadratic. • Quadratics will always have a variable raised to the second power, like x2. • Factoring is one way to find solutions to quadratic equations. 0 = x2 - 6x - 16 0 = (x - 8)(x + 2) x = {-2, 8}
x2 - 2x - 3 = 0 (x - 3)(x + 1) = 0 Set each factor to 0 x - 3 = 0 x = 3 x + 1 = 0 x = -1 x = -1 or x = 3 ¡ A. 1 and 3 ¡ B. -1 and -3 ¡ C. -1 and 3 ¡ D. 1 and -3 ¡ E. 1 and 2 D2. What are the solutions to the quadratic x2 - 2x - 3 = 0?
So what about the y = x2 - 2x - 3 graph? The graph Crosses The x axis Here
So what about the y = x2 - 2x - 3 graph? The graph Crosses The x axis Here x = -1
So what about the y = x2 - 2x - 3 graph? The graph Crosses The x axis Here x = -1 And here
So what about the y = x2 - 2x - 3 graph? The graph Crosses The x axis Here x = -1 And here x = 3
So what about the y = x2 - 2x - 3 graph? The graph Crosses The x axis Here x = -1 And here x = 3 So again we see our solution, x = -1 or x = 3
So what about the y = ax2 + bx + c graph? The graph Crosses The x axis Here x = ? And here x = ? This time we may need to use the quadratic formula