Substitution into Formulae − 2
Substitution can also be applied to letters that have indices
Example 1. What is the value of 2 + 3c2 when c = 4?
Example 2. What is the value of a + 7b2 when a = 2 and b = 5?
Example 3. What is the value of x + yz2 when x = −5, y = 4 and z = −6?
| 2 + 3c2 | = 2 + 3(42) |
| = 2 + (3 × 16) | |
| = 2 + 48 | |
| = 50 |
| a + 7b2 | = (2) + 7(52) |
| = 2 + (7 × 25) | |
| = 2 + 175 | |
| = 177 |
| x + yz2 | = (−5) + (4) (−6)2 |
| = −5 + (4 × 36) | |
| = −5 + 144 = 139 | |
| = 139 |
to: 
