| Factorise x² + 5x + 6 and verify the answer |
Reason: |
| = (x + 3)(x + 2) factors |
Factorise means to write the expression using factors. Each factor is put in a bracket. (x + 3) and (x + 2) are chosen because +3 and +2 add to +5 (number in front of the x term, known as the x coefficient) and they multiply to give +6 (the constant). |
| = x(x + 2) + 3(x + 2) |
We can check the factors are correct by multiplying out the brackets. Split the terms in the first bracket so that each multiplies by the second bracket. |
| = x² + 2x + 3x + 6 |
Remove the brackets. |
| = x² + 5x + 6 |
Add the x terms. This is the original expression. |