Linear Function
Linear functions are those whose graph is a straight line.
A linear function has one independent variable and one dependent variable.
Write a linear function with a slope of -9 and a y-intercept of 5
y =-9x+5
Which list contain points that lie on the graph of
y = 2x − 1?
a. (0, -1), (15, 29)
b. (-2, -4), (1, 3)
c. (-2, -3), (0, 0)
d. (2000, 1999), (3, 5)
a. (0, -1), (15, 29)
Identify the slope of the linear equation
y = -x + 6
The slope is -1
A line has a slope of 50 and a y-intercept of 3. What is the equation?
y=50x+3
What is Miss Perkins' other subject?
German
x-intercept and y-intercept
The x intercept is the point where the line crosses the x axis. At this point y = 0.
The y intercept is the point where the line crosses the y axis. At this point x=0
What are the basic steps to finding a point using a graph?
Find rise over run and y-intercept
What is the y - intercept of the graph of direct proportion?
y = 0 or (0, 0)
Find the slope of a line that passes through the points (0, 5) and (2, 10)
m = 5/2
Anthony is buying carrots and celery at the grocery store. The carrots cost $1.50 per kilo, x. He also forgot a bag and has to pay $1 for a reusable one.
What is the equation for the total cost (y) with respect to how many kilos of carrots (x)?
C=1.5x+1
What is the floral emblem of Queensland?
Cooktown orchard
Slope
the steepness of a line
Write the linear function in this graph:
y=20x-15
The given table shows a linear function.
What is the missing number in the table?
x 0 2 4 6
y -1 1 ? 5
3
What is the slope of the linear function
y = 14
0
If y is directly proportional to x and y=2 when x = 6. What is the constant of proportionality (k)?
1/3
What was Miss Perkins' first job?
Check out person at the Samford IGA
Name three synonyms for gradient
Rate, slope, proportion
Write a linear function that passes through the points (0,2) and (-4,5).
y= 3/4x +2
Would (2,-2) be a solution to the inequality
y ≤ 2x + 1?
Yes because if (2, -2), then
-2 ≤ 2(2) + 1
-2 ≤ 4 + 1
-2 ≤ 5
Since this is true, (2,-2) is a solution.
Find the slope of a linear function that contains the points (-2 , 8) and (5 , -13)
m=(-13-8)/(5-(-2))=-21/7
m=-3
T-Mobile charges $100 a month for a family plan for four people. They also charge a one time set up fee of $25. Write a function to show how much money a family spends in total after x months.
y=100x+25
How many gold medals did Australia win in the recent Winter Olympics?
1
Slope-Intercept Form
=y coordinate
=slope
=x coordinate
=y intercept
What are the basic steps to finding an equation using two points?
Find gradient and then sub in a point to find c
How could you write this equation in slope intercept form?
-2x + 3y = 12
y = 2/3x + 4
Write the equation of the table below.
x -1 2 5 8
y -2 7 16 25
y = 3x + 1
You are at school, 12 miles away from home. You start walking home with your friends at a speed of 3 miles per hour towards your home.
a. Write an equation that represents your distance from home (y) after (x) hours.
b. What does the slope of the equation represent?
c. What does the y-intercept of the equation represent?
a. y = -3x + 12
b. 3 miles per hour - walking closer to home (it is negative since the distance is getting shorter)
c. 12 miles away from home (the starting point)
What is Miss Perkins' dog's name?
Ned