GRAPHING FORMULAS Slope intercept y mx b ↓ Slope ↓ y-intercept Point – Slope y y1 m( x x1 ) Slope-Formula m y 2 y1 x 2 x1 How to label points: ( x1 , y1 )( x2 , y2 ) Standard Form of a Linear Equation ax by c c b y-intercept = Slope a b Standard Form of a Quadratic Equation ax 2 bx c 0 Vertex Form of a Quadratic Function f ( x ) a ( x h) 2 k where (h, k) is the vertex Quadratic Formula b b 2 4ac x 2a x Vertex Formula Discriminant Vertical Lines Horizontal Lines Parallel Lines Perpendicular Lines y x 2 y x 2x 1 2 2x 1 Circle Formula b 2a b 2 4ac Use the discriminant to determine the number & type of solutions to a quadratic equation. Positive = Two real solutions /Zero = One real solution / Negative = two complex, but not real solutions xN yN (Slope is undefined) (Slope = 0 ) Slopes are identical Slopes are negative reciprocals. (when you multiply the two slopes you get -1) a parabola that must go down because the Coefficient –x2 value is negative. a parabola that must go up because the x2 value is positive ( x h) 2 ( y k ) 2 r 2 Where (h, k) is the center and (x, y) is any point on the circle Midpoint Formula x1 x 2 y1 y 2 , 2 2 Distance Formula d x 2 x1 2 ( y 2 y 1 ) 2 Factoring: Cube Formulas (a b)(a 2 ab b 2 ) and (a b)(a 2 ab b 2 ) Saved: Math HANDOUT (Graphing Formulas) {Tutorial Support Services Mission del Paso Campus } sources: Textbook Algebra a Combined Approach by Elayn Martin-Gay (black cover)