1. 20Jan 2011 Warm UP– silently please 1) HOMEWORK DUE NEXT CLASS: pg. 289: 5, 9, 13 HINT: see examples on pg. 287-288 2)WARM UP- Do the parallel/ perpendicular handout

2. Objective Students will be able to find midpoint and slope to determine type of polygons. Homework Due TODAY Handout 11.1 #3-5 11.2 #1-2 Signed Syllabus Slip

3. Equation basics SLOPE FORMULA : Slope- Intercept Form of an Equation of a Line y = y 1 + m(x-x 1 ) y = mx + b Point- Slope Form of an Equation of a Line

4. review vocabulary median- a line segment of a triangle connecting a vertex to the midpoint of the opposite side altitude- a perpendicular segment from a vertex to the opposite side or a line containing the opposite side perpendicular bisector- a line that divides a line segment into two congruent parts and is perpendicular to the segment.

5. Using the point-slope formula Example: Given a point on a line and the slope, find the equation of the line: a) (2, 3) m = 2 y = y 1 + m(x-x 1 ) point-slope formula y = 3 + 2(x -2) substitute x 1 = 2, y 1 = 3 and m = 2 y = 3 + 2x – 4 distributive property y = 2x – 1 combine like terms

6. we can also use y =mx + b slope-intercept form of an equation of a line 3 = 2(2) + b substitute 3 = 4 + b evaluate -4 = -4 subtract 4 from both sides -1 = b Equation? y = 2x - 1 y = mx + b slope-intercept eqtn Example: Given a point on a line and the slope, find the equation of the line: a) (2, 3) m = 2

7. GROUPS- Each student must do work on their OWN paper. Work together to: DRAW your situation on graph paper Clearly show all your work BOX your answer EXPLAIN using A.B.E. The equation is…… because…..explain in words. Group 1: 3aGroup 2: 4a Group 3: 5aGroup 4: 4b Group 5: 3c Group 6: 5b Group 7: 4c Group 8: 3b BE READY TO PRESENT IN 10 MINUTES. HINTS: See examples, pg. 287 - 288