1. EASY SUBSTITUTION

2. This process is called substitution
Sometimes we are asked to evaluate (find the value of) an expression when we are given the numeric value of the letters
Evaluate a + 2 when a=4
a + 2
= 4 + 2
= 6
This process is called substitution

3. If b=3 give the value of:
2b + 5
= 2 x b + 5
= 2 x 3 + 5
= 6 + 5
= 11

4. If e=7 give the value of:
5e - 10
= 5 x e - 10
= 5 x =
= 25

5. If a= 5 and b=2 give the value of:
3a - 4b
= 3 x a - 4 x b
= 3 x x 2 =
= 7

6. If a=3, b=4 and c=2 give the value of:
a + 4c - b
= a + 4 x c - b
= x 2 - 4 =
= 7