Transcript Word Problems Notes

Bellwork
December 2 - 6
1. Solve for y:
4x – 2y = 10
2. Find the y-intercept in the equation
4x – 2y = 10.
An oil tank is being filled at a
constant rate. The table shows
that the depth of oil is a function
of the number of minutes the
tank has been filling.
x
y
Ex #1
1. Write an equation that represents the table.
Do I know my y-intercept?
2. Find the depth of oil after one half-hour.
1
y   30  3
5
y 9
9 feet
Helen is in a bicycle race.
She has already biked 10
miles and is now biking at a
rate of 18 miles per hour.
y
Her distance as a function
of time is shown in the
graph.
Ex #2
x
1. Write an equation to show the relationship
between the distance biked and the time in hours.
y  mx  b
y = 18 ● x + 10
y  18 x  10
Ex #2
Helen is in a bicycle race.
She has already biked 10
miles and is now biking at a
rate of 18 miles per hour.
y
Her distance as a function
of time is shown in the
graph.
y  18 x  10
x
2. Identify the slope and the y-intercept and
describe their meanings.
slope: 18
y-intercept: 10
Helen’s speed.
The distance she has already biked.
Ex #2
Helen is in a bicycle race.
She has already biked 10
miles and is now biking at a
rate of 18 miles per hour.
y
Her distance as a function
of time is shown in the
graph.
y  18 x  10
x
3. How far will Helen have biked after 3 hours?
y  18  3  10
64 miles
Toni is finishing a scarf at a
constant rate. The table
shows the number of hours
Toni has spent knitting this
week and the corresponding
number of rows in the scarf.
You Try
y
x
1. Write an equation in slope-intercept form to
represent this linear function.
Do I know my y-intercept?
You Try
Toni is finishing a scarf at a
constant rate. The table
shows the number of hours
Toni has spent knitting this
week and the corresponding
number of rows in the scarf.
y
x
1. Write an equation in slope-intercept form to
represent this linear function.
y  3x  b
38 = 3 ●2 + b
38 = 6 + b
-6 -6
32 = b
y  mx  b
y  3 x  32
Toni is finishing a scarf at a
constant rate. The table
shows the number of hours
Toni has spent knitting this
week and the corresponding
number of rows in the scarf.
You Try
x
y
2. How many rows has Toni knitted after 10 hours?
y  3 x  32
y  3  10  32
y  62
62 rows
A closet organizer charges a $100
initial consultation fee plus $30
per hour. The cost as a function of
the number of hours worked is
graphed below.
y
You Try
1. Write an equation that
represents the cost as a
function of the number of hours
worked.
y  mx  b
y = 30 ● x + 300
y  30 x  300
x
A closet organizer charges a $100
initial consultation fee plus $30
per hour. The cost as a function of
the number of hours worked is
graphed below.
y
You Try
2. Identify the slope and the yintercept and describe their
meanings.
y  30 x  300
slope: 30
y-intercept: 100
x
The amount charged per hour.
The initial fee.
A closet organizer charges a $100
initial consultation fee plus $30
per hour. The cost as a function of
the number of hours worked is
graphed below.
y
You Try
3. How much money will the
organizer make after 10 hours?
y  30 x  300
y  30  10  100
$400
x