When we factor a quadratic equation and the value of a is 1 (the coefficient for x² we can use a special strategy to solve it.

For example : if we has x² - 8x + 15 = 0

we can solve it by saying what numbers multiplied together = 15 and added together = -8. The answer is -5 and -3

For example : if we has x² + 7x + 10 = 0

we can solve it by saying what numbers multiplied together = 10 and added together = 7. The answer is 2 and 5

For example : if we has x² + 5x + 6 = 0

we can solve it by saying what numbers multiplied together = 6 and added together = 5. The answer is 2 and 3

For example : if we has x² - x - 2 = 0

we can solve it by saying what numbers multiplied together = -2 and added together = -1. The answer is -2 and 1

For example : if we has x² - 4x + 3 = 0

we can solve it by saying what numbers multiplied together = 3 and added together = -4. The answer is -3 and -1