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Expressions and Equations
HOW can a bar diagram
or algebra tiles help you
solve a real-world
problem?
Course 2, Inquiry Lab before Lesson 6-4
Expressions and Equations
• 7.EE.4
Use variables to represent quantities in a real-world or mathematical
problem, and construct simple equations and inequalities to solve problems
by reasoning about the quantities.
• 7.EE.4a
Solve word problems leading to equations of the form px + q = r and p(x +
q) = r, where p, q, and r are specific rational numbers. Solve equations of
these forms fluently. Compare an algebraic solution to an arithmetic solution,
identifying the sequence of the operations used in each approach.
Course 2, Inquiry Lab before Lesson 6-4
Common Core State Standards © Copyright 2010. National Governors Association Center for
Best Practices and Council of Chief State School Officers. All rights reserved.
Expressions and Equations
Mathematical Practices
1 Make sense of problems and persevere in solving them.
2 Reason abstractly and quantitatively.
3 Construct viable arguments and critique the reasoning of others.
4 Model with mathematics.
Course 2, Inquiry Lab before Lesson 6-4
Common Core State Standards © Copyright 2010. National Governors Association Center for
Best Practices and Council of Chief State School Officers. All rights reserved.
Expressions and Equations
Latoya play basketball and tennis. She has two basketballs and three
tennis balls that weight a total of 48 ounces. Each tennis ball weighs 2
ounces. What is the weight of the basketball?
You can use a bar diagram to represent the situation.
Draw a bar diagram that represents the total weight.
Activity 1
Continued
Course 2, Inquiry Lab before Lesson 6-4

Expressions and Equations
Latoya play basketball and tennis. She has two basketballs and three
tennis balls that weight a total of 48 ounces. Each tennis ball weighs 2
ounces. What is the weight of the basketball?
You can use a bar diagram to represent the situation.
Write an equation that is modeled by the bar diagram. Let x
represent the weight of a basketball.
Activity 1
Continued
Course 2, Inquiry Lab before Lesson 6-4

Expressions and Equations
Latoya play basketball and tennis. She has two basketballs and three tennis
balls that weight a total of 48 ounces. Each tennis ball weighs 2 ounces. What is
the weight of the basketball?
You can use a bar diagram to represent the situation.
Use the bar diagram to solve the equation. Subtract the weight of
the tennis balls,
ounces, from the total weight,
The two basketballs together weigh
Divide the weight by
So, x =
Check
+ 6 = 48 ✓
The weight of one basketball is
Course 2, Inquiry Lab before Lesson 6-4
, or
ounces.
to find the weight of one basketball.
. The weight of one basketball is
2•
–
ounces.
ounces.
÷
, or
ounces.
Expressions and Equations
You can use algebra tiles to model and solve the equation 4x – 2 = 10
Model the equation.
4x – 2 = 10
Activity 2
Continued
Course 2, Inquiry Lab before Lesson 6-4

Expressions and Equations
You can use algebra tiles to model and solve the equation 4x – 2 = 10
Add
1-tiles to each side of the mat to form zero pairs on the
left side.
4x – 2 + 2 = 10 + 2
Activity 2
Continued
Course 2, Inquiry Lab before Lesson 6-4

Expressions and Equations
You can use algebra tiles to model and solve the equation 4x – 2 = 10
Remove both zero pairs from the left side so that the variable is
by itself.
4x = 12
Activity 2
Continued
Course 2, Inquiry Lab before Lesson 6-4

Expressions and Equations
You can use algebra tiles to model and solve the equation 4x – 2 = 10
Divide the remaining tiles into
4 x 12
=
4
4
So, x =
Check
.
4•
– 2 = 10 ✓
Course 2, Inquiry Lab before Lesson 6-4
equal groups.
Expressions and Equations
HOW can a bar diagram
or algebra tiles help you
solve a real-world
problem?
Course 2, Inquiry Lab before Lesson 6-4