Alg 4.5 Day 2
Day 7
4.5 Parallel and Perpendicular Lines
Graph each of the equations on the graph to the right.
4
x 1
a) y 
b) 4x + 3y = 12
3
a) m = ________
b) m = ________
b = ________
b = ________
What do you notice?
The lines to the right are PERPENDICULAR:
Find their slopes by counting the graph. What do you notice?
(-1, 2)
(4, 1)
ma = _____________
mb =
(0, -2)
_____________
(2, -2)
BIG IDEA
When two lines have the ____________ ____________ then the lines are ____________________.
When two lines have ___________ _______________slopes, then the lines are __________________.
For 1-3, tell whether the graphs of the two equations are parallel, perpendicular, or neither:
1) y = 8x – 3,
3) y 
8x + y = 3
3
x  2 and -4x + 3y = 15
4
2) -10x + 2y = 7,
5x – y = 6
Day 13 – Graphing Comparison and Graphing – 3 Ways to Graph
COMPARISON
Graphing using a TABLE vs. INTERCEPTS vs. SLOPE- INTERCEPT FORM
Your Equation: 4x – 2y = 16
METHOD #1 – MAKE A TABLE
Graphing with a table: 4x – 2y = 16
x
y
Based on your graph what is the SLOPE of the line - _________
METHOD #2 – USING INTERCEPTS
x-intercept:
Find the intercepts : 4x – 2y = 16
y-intercept
Based on your graph what is the SLOPE of the line - _________
METHOD #3 – GRAPHING WITH SLOPE- INTERCEPT FORM
Show any work here:
4x – 2y = 16
m = ______
b = _______
WHEN DONE, WRITE A SENTENCE ABOUT WHAT YOU NOTICE WHEN LOOKING AT ALL 3 GRAPHS: