1. Section 1.3 Writing and Evaluating Expressions
Algebra Concepts
Section 1.3
Writing and Evaluating Expressions

2. Some Math Fun!!! Your shoe size can tell your age! Try this and see!
Use your calculator.

3. Step #1 Write down your shoe size
Step #1 Write down your shoe size. (no half sizes-round up) Step #2 Multiply the step #1 number by 5 Step #3 Add 50 to the step #2 number Step #4 Multiply the step #3 number by 20 Step #5 Add 1017 to the step #4 number Step #6 Subtract the year you were born from the step #5 number

4. 0814 Now look at your number in step six.
The first two digits are your shoe size and the last two digits are your age!
SO COOL!
0814

5. Warmup
Simplify #1 7(8−3) #2 16−4+10 #3 7+2∙6−3 #4 4 4 −2 +6÷3

6. Evaluate an algebraic expression
#1 Replace variables with the given numbers
Now you have a numerical expression!
#2 Simplify using order of operations

7. Evaluate 7𝑥+5 𝑓𝑜𝑟 𝑥=8
Step #1 WRITE THE PROBLEM!
Step #2 Substitute the number 8 in for the
variable.
Step #3 Simplify using order of operations

8. Answer
#1 7𝑥+5 𝑓𝑜𝑟 𝑥=8 # # MD 61 AS

9. Evaluate the following:
# abc for a=10, b=2, c=8
# 𝑚+7 3 −4 𝑓𝑜𝑟 𝑚=8
# 𝑥−𝑧 +6 𝑓𝑜𝑟 𝑥=10, 𝑧=3
SHOW ALL STEPS!!!

10. #1 abc for a=10, b=2, c=8 (10)(2)(8) (20)(8) MD 160 MD

11. #2 𝑚+7 3 −4 𝑓𝑜𝑟 𝑚=8 (8+7) 3 −4 15 3 −4 P 5−4 MD 1 AS

12. # 𝑥−𝑧 +6 𝑓𝑜𝑟 𝑥=10, 𝑧=3
3 10−3 +6 P MD AS

13. Joey can mow 9 lawns in a day.
Write a numerical expression for the number of lawns Joey can mow in 4 days.
Write an algebraic expression for the number of lawns Joey can mow in d days

14. Lesson quiz
#1 𝐸𝑣𝑎𝑙𝑢𝑎𝑡𝑒 7 𝑏 −4 𝑓𝑜𝑟 𝑏=3 #2 𝐸𝑣𝑎𝑙𝑢𝑎𝑡𝑒 ℎ÷2+1 𝑓𝑜𝑟 ℎ=12 #3 𝐸𝑣𝑎𝑙𝑢𝑎𝑡𝑒 3𝑐+4÷𝑑 𝑓𝑜𝑟 𝑐=8,𝑑=2 #4 𝐸𝑣𝑎𝑙𝑢𝑎𝑡𝑒 𝑓𝑔−𝑔 𝑓𝑜𝑟 𝑓=5,𝑔=7 #5 Pens are sold at the school store in packs of 4. Write an algebraic expression for the number of packages a student should buy to get p pens. Evaluate this expression for 12 pens.