Writing Two Variable Equations
Sam made some cookies (s).
Grant ate 5.
Write an equation for how many cookies are left (c).
c=s-5
Kim has $450 in the bank. After buying groceries, she has $398 left in her account. How much did she spend at the grocery store?
398 + d = 450
$52
Is the given number a solution to the equation?
y/2.5 = 1.95
y = 4.875
Yes
2.5 + y = 6.75
y = 4.25
Use a GCF to write an equivalent expression for:
3x + 30
3(x+10)
10m=t
It takes James 10 minutes to run every mile. The equations relates how many miles he is running to his total time running. What is the dependent variable? Why?
t
total time depends on how many miles he is going to run that day!
Mary ran 27 miles last week, which was three times as far as Jada ran. How far did Jada run?
3m=27
m=9 miles
s + 1/4 = 12 1/2
s = 12 1/4
15=3n
n=5
7(x+6)
7x+42
Leah's friends gave her 15 dollars this year. She received some cash from her grandparents as well. Write a two variable relationship that describes the total amount of money she received on her birthday.
15+ grandparents=total
15+g=t
On Thursday, Jen checked her sourdough starter. It weighed some grams. She added 15 grams of flour but took out 4 grams of starter. If it now weighs 87 grams, how much did it weigh when she first checked it?
76 grams
Write and solve an equation:
Andre's school has 20 clubs, which is five times as many as his cousin's school. His cousin's school has x clubs.
20=5x
x=4 Clubs
9 = k/9
k = 81
Fill in the blanks:
45+75
___ (3+ ___ )
15(3+5)
Ben had s money in the bank. He withdrew $104. Now he has m dollars. Write an equation to represent the relationship
s-104=m
Mrs. Jacobs purchased 48 ounces of candy for her class. Each student gets 4 ounces. How many students are in Mrs. Jacobs' class?
4x = 48
12 students
Is the given number a solution to the equation?
x + 12=15
x=27
no
p - 2/3 = 5/6
p = 1 1/2
What is the GCF of 20 and 50?
10
One penny has a mass of 2.5g each roll of pennies contains 50 pennies. White an equation with two variables to represent the relationships between total mass of the pennies and any number of penny rolls.
Total mass = penny rolls * 2.5 * 50
t=125r
Hilda can run one mile every 7 minutes. How far can she run in a total of 21 minutes? Write and solve the equation.
7x = 21
21 Miles
z/6 =12
z = 72
1/7c = 3
c = 21
Use a GCF to rewrite:
18c+6
___ ( ___ + ___ )
6 ( 3c + 1)