# Everyday Math Grade 1 Answers Unit 7 Subtraction Fact Strategies and Attributes of Shapes

## Everyday Mathematics 1st Grade Answer Key Unit 7 Subtraction Fact Strategies and Attributes of Shapes

Fact Families

Family Note
To day your child generated addition and subtraction facts from dominoes to create fact families. Fact families show related facts and help children relate addition to subtraction. Although most dominoes have two addition facts and two subtraction facts, children discussed fact families for doubles (for example, 4 + 4 = 8), which have only one addition fact and one subtraction fact.

Write the 3 numbers for each domino. Use the numbers to write a fact family.
Question 1.
Numbers: _______, _______, _______ Fact Family:
_______ – _______ = _______
_______ – _______ = _______
_______ + _______ = _______
_______ + _______ = _______

Numbers: 7, 5, 12

Fact Family:
12 – 7 = 5

12 – 5 =7

7 + 5 =12

5 + 7 = 12

Question 2.
Numbers: _______, _______, _______ Fact Family:
_______ – _______ = _______
_______ – _______ = _______
_______ + _______ = _______
_______ + _______ = _______

Numbers: 6, 9, 15

Fact Family:

15 – 6 = 9

15 – 9 = 6

6 + 9 = 15

9 + 6 = 15

Practice
Question 3.
Use a paper clip. Measure the lengths of two shoes.
My shoe: _______ paper clips
Someone else’s shoe: _______ paper clips
Whose shoe is longer? How much longer? _______ shoe is _______ paper clips longer.

My shoe: 3 paper clips
Someone else’s shoes: 2.5 paper clips

My shoe is longer. About 1/2 paper clip. My shoe is 1/2 paper clip longer.

Relating Special Addition and Subtraction Facts

Family Note
In recent lessons, children learned about fact families and how addition facts have related subtraction facts. In today’s lesson, your child solved subtraction problems by thinking about related addition facts, particularly with doubles and combinations of 10. For example, children might solve 18 – 9 = ☐ by thinking addition: 9 + ☐ = 18.

Write an addition fact, you can use to find the answer. Then write the answer in the blank.
Example: 16 – 8 = 8
8 + ________ = 16

Question 1.
6 – 3 = ________

3+3 = 6

Question 2.
10 – 7 = ________

3 + 7 = 10

Question 3.
12 – 6 = ________

6+6 = 12

Question 4.
10 – 1 = ________

1+9 = 10

Practice
Question 5.
Record the time you do each activity.  More Subtraction Fact Strategies

Family Note
This Home Link reviews some of the work your child has been doing in recent lessons that relates subtraction facts to addition facts. Encourage your child to include some subtraction names in the name-collection box in Problem 2. For example, a subtraction name for 14 is 16 – 2.
Also included in this Home Link are more Fact Triangles for further fact practice.

Question 1.
Write the 3 numbers for the domino. Use the numbers to write the fact family. Numbers: ________, ________, ________
Fact Family:
________ + ________ = ________
________ + ________ = ________
________ – ________ = ________
________ – ________ = ________

Numbers:

5, 8, 13

Fact Family:

5 + 8 =13

8 + 5 = 13

13 – 8 = 5

13 – 5 = 8

Question 2.
Write as many names as you can for 1 4. 10 + 4 =14

7 + 7 = 14

15 – 1 = 14

9 + 5 =14

20 – 6 = 14

Question 3.
Cross out the names that do not belong.  Practice
Question 4.
Circle the tens digit.
4 0
9 2
3 9 Attributes of Shapes

Family Note
Today your child explored attributes of shapes. Some attributes of shapes are color, size, or number of sides or corners. Encourage your child to look carefully at objects all around—not just geometric objects—and identify their attributes.

List three attributes of each shape.
Question 1. Color: White

Number of Angles: 6

Number of sides: 6

Question 2. Color: Gray

Number of Angles: 4

Number of sides: 4

Practice
Question 3.
Record the time. The time is 12:00 The time is 9:00

Exploring Attributes, Fractions, and Salute!

Family Note
Today your child explored the connection between addition and subtraction in the game Salute!, divided shapes in half, and further explored attributes of shapes. Children will continue working with shapes in future lessons. To prepare for this, help your child find objects with the shapes listed below.
Also included in this Home Link are more Fact Triangles for further fact practice.

Question 1.
Find something in your house that has a triangle on it. Write its name, or draw its picture.

A Slice of pizza has Triangle on it. Question 2.
Find something in your house that has a circle on it. Write its name, or draw its picture.

The clock in my house has Circle on it. Question 3.
Find something in your house that has a square on it. Write its name, or draw its picture.

Rubix cube in my house has square on it. Practice
Question 4.
What number do the base-10 blocks show? __________

53

Defining and Nondefining Attributes

Family Note
Today your child learned about the attributes that define triangles and rectangles, such as the numbers of sides and corners (also called vertices). Without these defining attributes, a shape cannot be a triangle or a rectangle. Children also learned about nondefining attributes of shapes, such as color and size.

Question 1.
Draw 2 different triangles. The triangles must have at least two attributes that are different. The two attributes that are different are Color and size.

Question 2.
Name the attributes that are different.

Color, Size and the ways in which they point are the attributes that are different.

Question 3.
Name the attributes that are the same.

Three sides, Three Vertices, Three angles, all sides are straight are the attributes that are same.

Practice
Question 4.
Solve.
2 + 5 = ________
________ = 5 + 2
3 + 7 + 8 = __________

7

7

18

“What’s My Rule?”

Family Note
Ask your child to explain what the function machine is doing to the “in” numbers before he or she fills in the missing “out” numbers. For example, in the first problem, the function machine is adding 1 to each of the “in” numbers.

Also included in this Home Link are more Fact Triangles. This set of Fact Triangles includes three blanks. Fill them with whatever facts your child would like to practice more.

Fill in the missing rule and numbers.
Question 1. Rule is +1 Question 2. Rule is -2 Question 3. Rule is -7 Practice
Solve.
Question 4.
4 + _______ = 8

4

Question 5.
10 = 6 + _______

4

Question 6.
________ = 8 – 1

7

“What’s My Rule?”

Family Note
Today your child talked about how mathematical rules can be used to help us solve other problems. After your child finds a rule for each problem below, name a few more in numbers and ask your child to use the rule to tell you what the out numbers would be.

Find the rules.
Question 1. The Rule is +1

Question 2. The Rule is -4

Question 3. The Rule is +6

Question 4. The Rule is -5

Practice
Question 5.
Cyrus started at 19 on his number line. He hopped backward and landed on 10.
How many hops did Cyrus make? ____________
Number model: ____________

Cyrus makes 9 hops

Number Model : 19-9 = 10

Family Note
In previous lessons, children solved “What’s My Rule?” problems in which they were asked to find outputs and rules. Today they solved problems in which they had to find inputs. Have your child share strategies for finding the input numbers in Problem 1 below.

Also included in this Home Link are more Fact Triangles. This last set of Fact Triangles are all blanks. Fill them with whatever facts your child would like to practice more.

Solve the “What’s My Rule?” problems. Complete the number sentences to check your answers.
Question 1. 7 + 7 = ________
________ + 7 = 13
0 + 7 = ________
________ + 7 = 1 7

7 + 7 = 14
6 + 7 = 13
0 + 7 = 7
10 + 7 = 1 7 Question 2. ________ – 6 = 7
________ – 6 = 0
________ – 6 = 9
________ – 6 = 4

13 – 6 = 7
6 – 6 = 0
15 – 6 = 9
10 – 6 = 4 Practice
Question 3. __________

50

Time on a Digital Clock

Family Note
In Unit 6, your child learned about the hour hand of a clock and how it moves as hours pass. Children told time on clocks that had only hour hands. In today’s lesson, your child learned about the minute hand. Children told time to the hour on analog clocks with hour hands and minute hands. They also learned to read the time on digital clocks.

Record the time.
Question 1. 3:00

Question 2. 11:00

Draw hands to show the time.
Question 3.  Question 4.  Practice
Question 5.
Write <, >, or =.
13 42
106 105
16 + 23 39