3.1
What is the y-intercept of the following equation?
y=5x-12
b=-12
y=4x+9
m= 4
What does it mean to be perfectly linear?
The line has a constant slope for all the data
What electronic tool can you use to find the regression equation of a line?
DESMOS
The equations tell total cost for a number months of a gym membership. Which gym is more expensive?
G1: y= 10x + 25
G2: y= 10x + 40
G2: y=10x +40
is more expensive
Which equation has the steepest slope?
A: y=-7x+3
B: y=12x +5
C: y=2x -1
You pay a 8$ entrance fee and $2 per ride fair.
Which equation is correct?
A: y= 2x - 8
B: y= 2x +8
C: y= -2x+8
B: y=2x +8
True or false?
The line of best fit should have about the same number of points above and below the line?
TRUE
How should you type your equation into Desmos to find the linear regression equation?
y1 ~ mx1 + b
The equations tell total cost for a number months of a gym membership. Which gym is less expensive?
G1: y= 15x + 20
G2: y= 11x + 20
G2: y= 11x +20
is less expensive
Solve the equation:
-2(x-3) = -(x+7)
x=13
Solve for the independent variable.
y=-7x+14
x= -(1/7)y + 2
OR
x=(y-14) / -7
True or False
Everyone's eyeball line of best fit should look the same.
False.
The lines should look VERY similar, but when eyeballing, everyone will have slightly different lines
When finding a slope-intercept form regression equation of data using Desmos, what does "r " equal when the line is perfectly linear?
r=1
How do you determine how to restrict the domain of the function when given a story problem?
Look at the content of the story problem to see if any number should be excluded because they don't make sense for the question.
Solve the equation:
5(x-2) = (3/4)(4x+16)
x=11
There is $500 in your account and you spend $10 a day on lunch.
Find an equation to fit the situation.
y=-10x + 500
*Make sure your slope is negative!
Find f(6) when,
f(x) = 1/2 x + 9
f(6)= 12
In Desmos, when finding your linear regression equation,
what does it mean if r=0.988
The data is NOT perfectly linear/ does NOT have a consistent slope
How do you determine how to restrict the range of a function?
Base the range on how the domain is restricted
Bananas sold separately are $0.60 each. A bushel of 5 bananas is $2.50. How much is each banana when sold as a bushel.
HINT: your answer should be less than $0.60.
$2.50= 5x
(x represents the price per banana in the bushel deal)
x=$2.50/5 = $0.50
Solve for the independent variable:
y=(1/8)x - (7/4)
*DAILY DOUBLE*
If the original equation tells:
total profit based on number of hours worked,
what does the answer equation mean in words?
x= 8y + 14
*DAILY DOUBLE*
Hours worked based on the total profit
Find the x value when g(x)= -4
g(x)= 2x - 10
x= 3
x: 9 , 14 , 19 , 24 , 39 , 34
y:100 , 130 , 140 , 160 , 200 , 215
y= 4.6 x + 58.6
Solve the system of equations.
y=5x-8
y=8x+10
x=-6
ordered pair:
(-6, -38)