Let’s solve each expression step by step. We are told to substitute the given value for the variable and then compute.
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Part A: Evaluate when x = 9
1)
x + 12
→ 9 + 12 =
21
2)
8 + x
→ 8 + 9 =
17
3)
20 + x
→ 20 + 9 =
29
4)
4 + x
→ 4 + 9 =
13
5)
x + 14 - 15
→ First, 9 + 14 = 23; then 23 - 15 =
8
6)
x - 3
→ 9 - 3 =
6
7)
1 + x
→ 1 + 9 =
10
8)
x - 1
→ 9 - 1 =
8
9)
x + 11
→ 9 + 11 =
20
10)
x + 6
→ 9 + 6 =
15
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Part B: Evaluate when y = 5
11)
y + 17
→ 5 + 17 =
22
12)
y + 18
→ 5 + 18 =
23
13)
y - 5
→ 5 - 5 =
0
14)
12 + y
→ 12 + 5 =
17
15)
y + 14 - 13
→ First, 5 + 14 = 19; then 19 - 13 =
6
16)
11 - y
→ 11 - 5 =
6
17)
y - 2
→ 5 - 2 =
3
18)
9 + y
→ 9 + 5 =
14
19)
y + 7
→ 5 + 7 =
12
20)
y + 15 - 5
→ First, 5 + 15 = 20; then 20 - 5 =
15
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All calculations have been double-checked.
Final Answer:
1) 21
2) 17
3) 29
4) 13
5) 8
6) 6
7) 10
8) 8
9) 20
10) 15
11) 22
12) 23
13) 0
14) 17
15) 6
16) 6
17) 3
18) 14
19) 12
20) 15
Parent Tip: Review the logic above to help your child master the concept of algebraic expressions and equations worksheet.
