1. Linear Equations in Two Variables Ms. Zuniga IB Math Studies 1 Room F239

2. I. Slope-Intercept Form y = mx + c m: slope/gradient = rise/run = Δy/Δx c: y-intercept

3. Gradient Positive Negative Zero (horizontal) y=# undefined (vertical) x=#

4. Point-gradient Form y – y 1 = m(x – x 1 )

5. Standard Form: Ax + By + C = 0 There can be no fractions or decimals (A, B, and C are integers) A must be greater than 0 Must be set = 0 The GCF of A, B, and C = 1

6. Graphing You should be able to graph: Given 2 points (plot the points and connect with a line) Given 1 point and gradient (first plot point and from that point follow the gradient) In slope-gradient form (put a pt. on the y-axis where the y-int is located, then from that pt. follow the gradient)

7. Writing Equations You should be able to write an equation: Given the y-intercept and gradient (just plug the values into the equation y = mx + c) Given the gradient and 1 point (substitute values of y, m and x to solve for c which is the y-intercept. Then rewrite the equation as y=mx + c) Given 2 points (find gradient first, choose 1 pt. to substitute values of y, m, and x as discussed above)

8. Parallel and Perpendicular Lines Parallel lines have the same gradient Perpendicular lines have negative reciprocal gradients