Date: 10/11/16
Title: Writing Equations from Word Problems
Obj: To take real world examples and create
slope intercept equations.
Warm Up:
Get out your wonderful, colorful
review packet/small booklet. Be
ready for a homework check
and a quiz!!
Now on to writing equations from
word problems. We are going to
see them in two ways today:
Slope Intercept Form:
Standard Form:
y = mx + b
Ax + By = C
Slope Intercept Form:
what
we do
**Put this in your notebook**
y = mx + b
start
value
Standard Form:
Ax + By = C
two different
objects
Total or
end value
Let's look at a few together:
1. The cost of a school banquet is $95 plus
$15 for each person attending. Write an
equation that gives total cost as a function
of the number of people attending.
What is the start value?
What is the per amount? or the steady increase?
What does the x-value represent?
What does the y-value represent?
What is the cost for 77 people to attend?
Now it's your turn
2. Roman paid $150 to join a handball club. He pays
an additional $15 every time he uses one of the club's
handball courts.
What is the start value?
What is the per amount? or the steady increase?
What does the x-value represent?
What does the y-value represent?
If he uses the courts 13 times, what is the cost?
3. A water tank is full with 55 gallons of water. There is
a small leak and over time is loses 0.6 gallons each
day.
What is the start value?
What is the per amount? or the steady increase?
What does the x-value represent?
What does the y-value represent?
How much water will be in the tank after 36 days?
4. Members of the soccer team are walking to raise
money for a local shelter. Some sponsors pledged $3 per
kilometer. Other sponsors gave additional donations
that did not depend on the distance walked. Their total
donation given was $256.
What is the start value?
What is the per amount? or the steady increase?
What does the x-value represent?
What does the y-value represent?
They want to raise $842, how many kilometers
will they need to walk??
5. The graph for a stable that charges a $20 flat fee plus
$10 per hour for horseback riding is shown below. How
will the graph change if the stable changes its charge
to a flat fee of $45 plus $30 per hour?
6. The admission fee at a small fair is $1.50
for children and $4.00 for adults. On a
certain day, $5,050 is collected. Write a
linear equation to represent the situation.
What are the two objects being compared?
What is the total amount?
What does x and y represent?
If 1000 adults attended the fair, how many
children attended?
7. A road side vegetable stand sells
pumpkins for $5 each and tomatoes for $3
each. The total sales on a certain day was
$98. Write an equation to represent the
situation.
What are the two objects being compared?
What is the total amount?
What does x and y represent?
If they sold 10 pumpkins, find the number of
tomatoes sold.
8. A tire dealer sells Supreme tires for $48
each and Prestige tires for $56 each. During
the week, the sales for both tires totaled
$2008. Write an equation to represent this
situation.
What are the two objects being compared?
What is the total amount?
What does x and y represent?
If 11 Prestige tires were sold, find the number of
Supreme tires sold.
**Challenge**
A grocer knows that if he sells his canned hams for $8
each, he can sell 950 per month, and if he sells the
same hams for $10, he will sell 900 per month.
Assuming the relationship between price and sales is
linear, write an equation to predict the sales for other
prices.
Homework:
Handout from class.
Quiz corrections by Thursday.