## Math Expressions Common Core Grade 1 Unit 3 Lesson 1 Answer Key Explore Unknowns

**Math Expressions Grade 1 Unit 3 Lesson 1 Homework**

**Find the unknown partner.**

Question 1.

Answer:

Explanation:

4 is the partner for given number 4.

since sum of 4 and 4 is 8.

So answer is 4.

Equation: 4+4=8

Question 2.

Answer:

Explanation:

2 is the partner for given number 5.

since sum of 2 and 5 is 7.

So answer is 2.

Equation: 5+2=7

Question 3.

Answer:

Explanation:

4 is the partner for given number 6.

since sum of 4 and 6 is 10.

So answer is 4.

Equation: 4+6=10

Question 4.

Answer:

Explanation:

1 is the partner for given number 5.

since sum of 5 and 1 is 6.

So answer is 1.

Equation: 5+1=6

Question 5.

Answer:

Explanation:

5 is the partner for given number 4.

since sum of 4 and 5 is 9.

So answer is 5.

Equation: 4+5=9

Question 6.

Answer:

Explanation:

3 is the partner for given number 7.

since sum of 3 and 7 is 10.

So answer is 3.

Equation: 3+7=10

Question 7.

Answer:

Explanation:

6 is the partner for given number 1.

since sum of 1 and 6 is 7.

So answer is 6.

Equation: 1+6=7

Question 8.

Answer:

Explanation:

2 is the partner for given number 6.

since sum of 2 and 6 is 8.

So answer is 2.

Equation: 6+2=8

Question 9.

Answer:

Explanation:

8 is the partner for given number 2.

since sum of 2 and 8 is 10.

So answer is 8.

Equation: 2+8=10

Question 10.

Answer:

Explanation:

4 is the partner for given number 2.

since sum of 4 and 2 is 6.

So answer is 4.

Equation: 2+ 4=6

Question 11.

Answer:

Explanation:

6 is the partner for given number 3.

since sum of 6 and 3 is 9.

So answer is 6.

Equation: 6+3=9

Question 12.

Answer:

Explanation:

1 is the partner for given number 4.

since sum of 4 and 1 is 5.

So answer is 1.

Equation: 4+1=5

**Math Expressions Grade 1 Unit 3 Lesson 1** **Remembering**

**Write the partners.**

Question 1.

Answer:

Explanation:

Written the partners of 5

**Write the partners and total for each circle drawing.**

Question 2.

Answer:

Explanation:

We have 8 black circles and 2 white circles.

So the total of black and white circles are 10

Equation: 8 +2 = 10

Question 3.

Answer:

Explanation:

We have 6 black circles and 3 white circles.

So the total of black and white circles are 9.

Since sum of 6 and 3 is 9.

Equation: 6 +3 = 9

**Write the partners and the total. Then write the equation.**

Question 4.

Answer:

Explanation:

We have 5 black circles and 3 white circles.

So the total of black and white circles are 8.

Since sum of 5 and 3 is 8.

Equation: 5 +3 = 8

Question 5.

**Stretch Your Thinking** Write on addition equation to help solve 9 – 2 = ___.

Answer:

7 + 2 = 9

Explanation:

We have 7 black circles and 2 white circles.

So the total of black and white circles are 9.

Since sum of 7 and 2 is 9.

Equation: 7 +2 = 9