1. Substituting into Algebraic Equations
Graphics used are from MS clipart

2. Evaluate if
Every time you see an “x” you replace it with (-6) and then solve. -6
+ 3
=-3
Think of tiles: 6 white tiles add 3 red tiles. Take out the ones that match up and you have 3 white tiles left or -3

3. + 3 – n 3 – (-6) 3 + 6 = 9 Evaluate if n = -6
Minus and a minus give you a +
Rewrite the question with a single +

4. 3p – 2q 3(8) – 2(3.5) 24 - 7 = 17 Two Substitutions
Solve if p is 8 and q is 3.5
This time you must make two substitutions. Where there is a p, you substitute with an 8 and where there is a q, you substitute with 3.5
3p – 2q
3(8) – 2(3.5)
24 - 7
= 17

5. Now try these where: p=8 and q=3.5
p + 3q
5p – 6q
2p + 10q
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6. Which expressions have the same value when m=4?
b) 30 – 5m
c) 2m + 3
d) m + 8 2
e) 21 – 2m
f) 5(m+2) 3
g) 8m – 5m -1
h) 3m – m + 2
Enter the letters of the expressions that have the same value!
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