6th Grade Math Textbook, Progress

Addition Equations

4-5

The seating capacity for football games at a sports

stadium is 4117 more than the seating capacity for

baseball games. If the seating capacity is 63,000

for football games, what is the seating capacity for

baseball games?

To find the seating capacity for baseball games,

write and solve an equation.

Let xrepresent the seating capacity for

baseball games.

seating capacity seating capacity

for baseball plus 4117 equals for football

x 
 4117  63,000

To solve an addition equation,use

the Subtraction Property of Equality.

addition equation

x
 4117 63,000

x
 4117  4117 63,000 4117

x58,883

Subtract 4117

from both sides

to isolate the

variable.

Subtraction Property of Equality

When you subtract the same

number from both sides of an

equation, you get a true

statement.

Check: x
 4117 63,000

58,883
 4117 

?

63,000

63,00063,000 True

The seating capacity for baseball games is 58,883.

Study this example.

Solve: 27.5y
3.3
1.7

27.5y
3.3
1.7

27.5y
5.0

27.55.0y
5.05.0

22.5y

Check: 27.522.5
3.3
1.7

27.5 

?

22.5
5.0

27.527.5 True

Simplify by adding the numbers on one side.

Subtract 5.0 from both sides to isolate the variable.

Remember: Addition and

subtraction are inverse

operations.

Update your skills. See page 7.

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