All the solutions provided in **McGraw Hill Math Grade 2 Answer Key PDF Chapter 1 Lesson 9 Use Doubles to Subtract** will give you a clear idea of the concepts.

## McGraw-Hill My Math Grade 2 Answer Key Chapter 1 Lesson 9 Use Doubles to Subtract

**Explore and Explain**

**Teacher Directions:** Place a 6 cube train at the top of the page. Trace it. Separate the train into two equal parts. Draw the parts below the 6 cube train. Write how many cubes are in each part.

Explanation:

**See and Show**

You can use doubles facts to help you subtract.

Find 16-8.

**Use cubes and doubles facts to subtract.**

Question 1.

9 + ____ = 18

18 – 9 = ____

Answer:

9 + 9 = 18

18 – 9 = 9

Explanation:

Two addends that are the same are called doubles.

Double Facts are additions in which a number is added to itself.

The difference of 18 and 9 is 9

Question 2.

5 + ____ = 10

10 – 5 = ____

Answer:

5 + 5 = 10

10 – 5 = 5

Explanation:

Two addends that are the same are called doubles.

Double Facts are additions in which a number is added to itself.

The difference of 10 and 5 is 5

Question 3.

6 + ___ = 12

12 – 6 = ___

Answer:

6 + 6 = 12

12 – 6 = 6

Explanation:

Two addends that are the same are called doubles.

Double Facts are additions in which a number is added to itself.

The difference of 12 and 6 is 6

Question 4.

4 + ____ = 8

8 – 4 = ____

Answer:

4 + 4 = 8

8 – 4 = 4

Explanation:

Two addends that are the same are called doubles.

Double Facts are additions in which a number is added to itself.

The difference of 8 and 4 is 4

Question 5.

7 + ___ = 14

14 – 7 = ___

Answer:

7 + 7 = 14

14 – 7 = 7

Explanation:

Two addends that are the same are called doubles.

Double Facts are additions in which a number is added to itself.

The difference of 14 and 7 is 7

Question 6.

8 + ____ = 16

16 – 8 = ____

Answer:

8 + 8 = 16

16 – 8 = 8

Explanation:

Two addends that are the same are called doubles.

Double Facts are additions in which a number is added to itself.

The difference of 16 and 8 is 8

**Talk Math** Explain how you can use a doubles fact to subtract.

**Helpful Hint**

I know 5 + 5 = 10, so 10 – 5 = 5.

**On My Own**

**Subtract. Circle the doubles facts.**

Question 7.

9 – 3 = ___

Answer:

6

Explanation:

The difference of 9 and 3 is 6

9 – 3 = 6

Question 8.

11 – 9 = ____

Answer:

2

Explanation:

The difference of 11 and 2 is 9

11 – 9 = 2

Question 9.

6 – ___ = 3

Answer:

6 – 3 = 3

3 + 3 = 6

Explanation:

The difference of 6 and 3 is 3

Question 10.

7 – 3 = ____

Answer:

4

Explanation:

The difference of 7 and 3 is 4

7 – 3 = 4

Question 11.

18 – 9 = ___

Answer:

9

Explanation:

The difference of 18 and 9 is 9

18 – 9 = 9

Question 12.

15 – 7 = ____

Answer:

8

Explanation:

The difference of 15 and 7 is 8

15 – 7 = 8

Question 13.

Answer:

Explanation:

The difference of 16 and 8 is 8

16 – 8 = 8

Question 14.

Answer:

Explanation:

The difference of 7 and 0 is 7

7 – 0 = 7

Question 15.

Answer:

Explanation:

The difference of 10 and 5 is 5

10 – 5 = 5

Question 16.

Answer:

Explanation:

The difference of 9 and 8 is 1

9 – 8 = 1

Question 17.

Answer:

Explanation:

The difference of 6 and 2 is 4

6 – 2 = 4

Question 18.

Answer:

Explanation:

The difference of 8 and 3 is 5

8 – 3 = 5

Question 19.

Answer:

Explanation:

The difference of 14 and 7 is 7

14 – 7 = 7

Question 20.

Answer:

Explanation:

The difference of 7 and 6 is 1

7 – 6 = 1

Question 21.

Answer:

Explanation:

The difference of 8 and 4 is 4

8 – 4 = 4

**Problem Solving**

Question 22.

Fran and her grandmother pick 16 pumpkins. They use 8 pumpkins for pie. How many pumpkins are left?

____ pumpkins

Answer:

8 pumpkins

Explanation:

Fran and her grandmother pick 16 pumpkins.

They use 8 pumpkins for pie.

16 – 8 = 8

8 pumpkins are left.

Question 23.

Delia bakes 18 cherry pies. She sells 9 pies at a farmers’ market. How many pies does Delia have left?

____ pies

Answer:

9 pies.

Explanation:

Delia bakes 18 cherry pies.

She sells 9 pies at a farmers’ market.

18 – 9 = 9

9 pies that Delia have left.

Question 24.

14 children were playing hide and go seek. 7 children were found. How many children are still hiding?

____ children

Answer:

7 children.

Explanation:

14 children were playing hide and go seek.

7 children were found.

14 – 7 = 7

7 children are still hiding.

**Write Math** Explain how you can use doubles facts to help you subtract.

### McGraw Hill My Math Grade 2 Chapter 1 Lesson 9 My Homework Answer Key

**Practice**

**Subtract. Circle the doubles facts.**

Question 1.

18 – 9 = ____

Answer:

9

Explanation:

The difference of 18 and 9 is 9

18 – 9 = 9

Question 2.

6 – 2 = ____

Answer:

4

Explanation:

The difference of 6 and 2 is 4

6 – 2 = 4

Question 3.

8 – 2 = ___

Answer:

6

Explanation:

The difference of 8 and 2 is 6

8 – 2 = 6

Question 4.

5 – 3 = ____

Answer:

2

Explanation:

The difference of 5 and 3 is 2

5 – 3 = 2

Question 5.

16 – 8 = ___

Answer:

8

Explanation:

The difference of 16 and 8 is 8

16 – 8 = 8

Question 6.

8 – 3 = ___

Answer:

5

Explanation:

The difference of 8 and 3 is 5

8 – 3 = 5

Question 7.

6 – 3 = ___

Answer:

3

Explanation:

The difference of 6 and 3 is 3

6 – 3 = 3

Question 8.

8 – 8 = ___

Answer:

0

Explanation:

The difference of 8 and 8 is 0

8 – 8 = 0

Question 9.

Answer:

Explanation:

The difference of 14 and 7 is 7

14 – 7 = 7

Question 10.

Answer:

Explanation:

The difference of 9 and 1 is 8

9 – 1 = 8

Question 11.

Answer:

Explanation:

The difference of 10 and 4 is 6

10 – 4 = 6

**Subtract. Circle the doubles facts.**

Question 12.

14 – 6 = ____

Answer:

8

Explanation:

The difference of 14 and 6

14 – 6 = 8

Question 13.

18 – 8 = ____

Answer:

10

Explanation:

The difference of 18 and 8 is 10

18 – 8 = 10

Question 14.

18 – 9 = ___

Answer:

9

Explanation:

The difference of 18 and 9 is 9

18 – 9 = 9

Question 15.

15 – 7 = ___

Answer:

8

Explanation:

The difference of 15 and 7 is 8

15 – 7 = 8

Question 16.

Anita checks out 14 library books. She reads 7 of the books. How many books does she still have to read?

____ books

Answer:

7 books

Explanation:

Anita checks out 14 library books.

She reads 7 of the books.

14 – 7 = 7

7 books that she still have to read.

Question 17.

Lindsay has 16 cupcakes to hand out. She has given 8 to the girls in her class. How many does she have left?

___ cupcakes

Answer:

8 cup cakes.

Explanation:

Lindsay has 16 cupcakes to hand out.

She has given 8 to the girls in her class.

16 – 8 = 8

she have left 8 .

**Test Practice**

Question 18.

Mark the number sentence that uses doubles.

(A) 4 – 4 = 0

(B) 8 – 4 = 4

(C) 8 – 3 = 5

(D) 8 – 8 = 0

Answer:

A and D

Explanation:

4 – 4 = 0

8 – 8 = 0

Options A and D uses the doubles.

**Math at Home** Call out doubles facts. Have your child name the subtraction problem for each double.