Upload
lexi
View
34
Download
0
Embed Size (px)
DESCRIPTION
TYPES OF RELATIONS. LINEAR RELATIONS:. the graph is a straight line the rate of change “a” is constant (the rate of change between any 2 points on the line will be the same). RELATION 1 – CONSTANT FUNCTION. - PowerPoint PPT Presentation
Citation preview
TYPES OF RELATIONS
LINEAR RELATIONS:
the graph is a straight line the rate of change “a” is constant (the
rate of change between any 2 points on the line will be the same)
RELATION 1 – CONSTANT FUNCTION Consider the amount of fuel purchased and
the price per litre. (Gas is 98.9 cents per litre)
Table of ValuesAmount (L)
1 5 10 15 … x
Price per Litre (¢)
98.9
RELATION 1 Consider the amount of fuel purchased and
the price per litre. (Gas is 98.9 cents per litre)
Table of ValuesAmount (L)
1 5 10 15 … x
Price per Litre (¢)
98.9 98.9 98.9 98.9 … 98.9
GRAPH ..straight line parallel to x-axis
Amount (L)
Price per Litre (¢)
0 5 10 15
100
75
50
25
Price of Fuel
RULEThe rule is:
cost per litre = 98.9 ¢The rule is y = 98.9 ¢
Table of ValuesNo matter what the x value is..the
y value always stays the SAME
The cost per litre is constant
The rate of change is zero (a = 0)
We call this a ZERO VARIATION relation
The rule is: y = b (constant value) y = 98.9
DO..WORKBOOK PAGE 107-108 ACTIVITY 2 COST OF BUS RIDEDO..A,B,C,D,E,FPAGE 116 #8PAGE 143 #2TEXTBOOK #1PAGE 153 #4BRING TEXTBOOK #2 FROM NOW ON
RELATION 2 – DIRECT VARIATION The cost of apples is $2.50 per kg.
Independent variable: number of kg you buy
Dependent variable: cost of buying apples
RELATION 2 – DIRECT VARIATION The cost of apples is $2.50 per kg.
Independent variable: # of kg of apples
Dependent variable: cost ($)
TABLE OF VALUES
Amount (kg)
0 1 2 5 … x
Cost ($)
TABLE OF VALUES
Number of kg purchased
0 1 2 5 … x
Cost ($) 0 2.50 5.00 12.50
TABLE OF VALUES
Cost = 2.50 times the amount of kg purchased y = 2.50 x dep r.o.c indep
Rule for direct y = a xRule for this question: y=2.50x
Number of kg purchased
0 1 2 5 … x
Cost ($) 0 2.50 5.00 12.50 2.50 xRULE
GRAPH
Amount (kg)
Cost ($)
0 1 2 3
10.007.505.002.50
Cost of Apples
DIRECT VARIATIONThere is no initial fee (start-up cost)Values are proportional (you can
cross multiply and always get the same answer)
The rule is y = ax (“a” is the rate of change) y is dep var, x is indep. var
The graph is a straight line that passes through the origin
WORK ON ZERO AND DIRECT RELATIONS WorkbookPage 116 #8,9
Text #2Page 101 #1Page 102 #4a-h, #5Page 103 #6, 7Page 104 #9 (find the rate of change first then
write it in the rule y = ax
QUIZ ON RATE OF CHANGE…TAKE OUT A PIECE OF PAPER..PUT YOUR NAME ON IT…
Calculate the rate of change…write coordinates, label, write the formula, solve for the r.o.c
1- (2,10) (6,30) a =5
2- (-2,4) (5,-2) a= -6/7
3.- ( 1,8) (8,8) a= o
4- (26,12) (102,50)a= 38/76 or 1/2
5- (24,4) (12,8) a= -4/12 or -1/3