All the solutions provided in McGraw Hill My Math Grade 1 Answer Key PDF Chapter 2 Lesson 13 Relate Addition and Subtraction will give you a clear idea of the concepts.
McGraw-Hill My Math Grade 1 Answer Key Chapter 2 Lesson 13 Relate Addition and Subtraction
Explore and Explain
Answer:
Explanation:
There are 3 birds in the bird bath
2 more birds join them
The addition fact to solve the problem is 3 + 2 = 5
The related subtraction fact is 5 – 3 = 2
So, there are 5 birds in all.
Teacher Directions: Use 
to model. There are 3 birds in the bird bath. 2 more birds join them. Write the addition number sentence to show how many birds there are in all. Write a related subtraction number sentence.
See and Show
Related facts use the same numbers. These facts can help you add and subtract
5 + 2 = 7
7 – 5 = 2
7 – 2 = 5
Helpful Hint
5 + 2 = 7.
Use that fact to find
7 – 2 = 5.
You can use 5 + 2 = 7
to find 7 – 2 = 5
They are opposite or inverse operations.
Identify an addition fact. Use Work Mat 3 and 
to find a related subtraction fact. Write both facts.
Question 1.
____ + ____ = _____
____ – ____ = _____
Answer:
3 + 6 = 9
9 – 3 = 6
Explanation:
The addition fact for the given picture is 3 + 6 = 9
The related subtraction fact is 9 – 3 = 6.
Question 2.
____ + ____ = _____
____ – ____ = _____
Answer:
2 + 4 = 6
6 – 2 = 4
Explanation:
The addition fact for the given picture is 2 + 4 = 6
The related subtraction fact is 6 – 2 = 4.
Talk Math How can addition facts help you subtract? Explain.
Answer:
We can use addition fact to subtract by subtracting one of the addend from the sum.
On My Own
Use Work Mat 3 and to find the related subtraction facts. Write the facts.
Question 3.
5 + 4 = 9
____ – ____ = ____
____ – ____ = ____
Answer:
9 – 4 = 5
9 – 5 = 4
Explanation:
The related subtraction facts for the given addition facts are 9 – 4 = 5 and 9 – 5 = 4.
Question 4.
8 + 1 = 9
____ – ____ = ____
____ – ____ = ____
Answer:
9 – 1 = 8
9 – 8 = 1
Explanation:
The related subtraction facts for the given addition facts are 9 – 1 = 8 and 9 – 8 = 1.
Question 5.
1 + 4 = 5
____ – ____ = ____
____ – ____ = ____
Answer:
5 – 1 = 4
5 – 4 = 1
Explanation:
The related subtraction facts for the given addition facts are 5 – 1 = 4 and 5 – 4 = 1.
Question 6.
3 + 4 = 7
____ – ____ = ____
____ – ____ = ____
Answer:
7 – 3 = 4
7 – 4 = 3
Explanation:
The related subtraction facts for the given addition facts are 7 – 3 = 4 and 7 – 4 = 3.
Question 7.
5 + 3 = 8
____ – ____ = ____
____ – ____ = ____
Answer:
8 – 5 = 3
8 – 3 = 5
Explanation:
The related subtraction facts for the given addition facts are 8 – 5 = 3 and 8 – 3 = 5.
Question 8.
2 + 3 = 5
____ – ____ = ____
____ – ____ = ____
Answer:
5 – 2 = 3
5 – 3 = 2
Explanation:
The related subtraction facts for the given addition facts are 5 – 2 = 3 and 5 – 3 = 2.
Problem Solving
Write a subtraction number sentence. Then write a related addition fact.
Question 9.
There are 8 lizards. 6 of the lizards run away. How many lizards are left?
____ – ____ = ____ lizards
____ + ____ = ____
Answer:
8 – 6 = 2 lizards
6 + 2 = 8
Explanation:
There are 8 lizards
6 of the lizards run away
The subtraction fact to solve the problem is 8 – 6 = 2
The addition fact for the problem is 6 + 2 = 8
So, 2 lizards are left.
Question 10.
Chad saw 7 birds. Audrey saw 4 birds. How many more birds did Chad see?
____ – ____ = ____ birds
____ + ____ = ____
Answer:
7 – 4 = 3 birds
4 + 3 = 7
Explanation:
Chad saw 7 birds
Audrey saw 4 birds
The subtraction fact to solve the problem is 7 – 4 = 3
The addition fact for the problem is 4 + 3 = 7
So, Chad see 3 more birds.
Write Math 5 + 4 = 9 and 9 – 3 = 6. Are these related facts? Explain why or why not.
______________________
______________________
______________________
______________________
Answer:
5 + 4 = 9 and 9 – 3 = 6
No, these are not related facts
In related facts the facts will have same numbers.
McGraw Hill My Math Grade 1 Chapter 2 Lesson 13 My Homework Answer Key
Practice
Identify an addition fact. Write a related addition and subtraction fact.
Question 1.
____ + ____ = _____
____ – ____ = _____
Answer:
4 + 3 = 7
7 – 4 = 3
Explanation:
The addition fact for the given picture is 4 + 3 = 7
The related subtraction fact is 7 – 4 = 3.
Question 2.
____ + ____ = _____
____ – ____ = _____
Answer:
3 + 5 = 8
8 – 3 = 5
Explanation:
The addition fact for the given picture is 3 + 5 = 8
The related subtraction fact is 8 – 3 = 5.
Find the related subtraction facts. Write the facts.
Question 3.
4 + 2 = 6
____ – ____ = _____
____ – ____ = _____
Answer:
6 – 2 = 4
6 – 4 = 2
Explanation:
The related subtraction facts for the given addition facts are 6 – 2 = 4 and 6 – 4 = 2.
Question 4.
1 + 8 = 9
____ – ____ = _____
____ – ____ = _____
Answer:
9 – 1 = 8
9 – 8 = 1
Explanation:
The related subtraction facts for the given addition facts are 9 – 1 = 8 and 9 – 8 = 1.
Write the subtraction number sentence. Then write the related addition fact.
Question 5.
There are 6 flowers in a vase. Mom gives 2 of the flowers to a friend. How many flowers are in the vase now?
____ – ____ = ____
____ + ____ = ____
Answer:
6 – 2 = 4
4 + 2 = 6
Explanation:
There are 6 flowers in a vase
Mom gives 2 of the flowers to a friend
6 – 2 = 4
The subtraction fact to solve the problem is 6 – 2 = 4
The addition fact for the problem is 4 + 2 = 6.
Vocabulary Check
Circle the correct answerÂ
subtract     related facts
Question 6.
3 + 1 = 4 and 4 – 1 = 3 are ______
Answer:
related facts
Explanation:
3 + 1 = 4 and 4 – 1 = 3 are related facts.
Math at Home Write an addition or subtraction number sentence using numbers 1-9. Have your child write a related addition or subtraction fact.