1. Unit 1. Day 9.

2. Please get out paper for today’s lesson
Name
Date
Period
Topic: Evaluating Expressions
7.NS.A.3 Solve real‐world and mathematical problems involving the four operations with rational numbers.

3. What is an expression? 3𝑥 2𝑥−1=8 6 4 −9+1 2− 1−8÷4 3 2+3=5 2− 5 2
6 4 −9+1 2− 1−8÷4 3
2+3=5
2− 5 2
A math “sentence”
(without an equal sign)

4. Example A: −2
Evaluate the expression if 𝑎 = −2 , 𝑏 = 4, and 𝑐 = −9 4 −9
𝑎𝑏−3𝑐 − 3 −8
−3 −9 −8
+27 19

5. Example B*:
Evaluate the expression if 𝑑 =3 , 𝑒 =−6, and 𝑓 = −8 3 −6 −8
𝑒 2 ÷𝑑−𝑓 2 2 ÷ − 36
÷ 3 − −8 + 12
− −8 20

6. Example C:
Evaluate the expression if 𝑥 = −8 , 𝑦 =−3, and 𝑧 =1 −8 −3
2𝑥+4 9−𝑦 −
+ 4
−16 +
9− −3
−12 12 −1

7. Evaluate the expression if 𝑝=4, q=−3, 𝑟=−5, 𝑠=−1, and 𝑡=6
7𝑟 − 2 𝑝 + 𝑡 𝑞
Example D:
𝑞𝑟− 𝑠 4 𝑟𝑡+𝑝𝑞
Example E:

8. Example D: 𝑝=4, q=−3, 𝑟=−5, 𝑠=−1, and 𝑡=6 −3 −5 6 7 − 2 +−
7𝑟 − 2 𝑝 + 𝑡 𝑞
7 −5 − −3 16
− −3
−35
−35−16+ −2
−51 −2
−53

9. Example E: 𝑝=4, q=−3, 𝑟=−5, 𝑠=−1, and 𝑡=6 4 −3 −3 −5 −5 −1 6 14 + 4 −3−3
𝑞𝑟− 𝑠 4 𝑟𝑡+𝑝𝑞 −
−30 +
14 −30+
−3 −5 − − −3 1
−12
−1 − −3 15 14
−42 14
− 1 3
− −3