## FANDOM

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A quadratic expression is an expression with a highest power of x, as 2 or an equation with degree 2 and the general form is:

ax2 + bx+c where a, b and c are numbers.

## Type 1 Edit

(For an expression with a coefficient of x equal to 1, (a=1), the given method can be used to factorise)

Method

1. Find 2 factors of the Constant Term (c), which should add to a coefficient of x
2. Write the xpression as a product of two brackets, with a factor in each bracket

Examples

1. Factorize x2 + 5x + 6
• Factors of 6 that add to 5:
• ​2 * 3 = 6
• 2 + 3 = 5
• Answer: (x + 2)(x + 3) OR (x + 3)(x + 2)
2. Factorize x2 - 12x + 36
• Factors of 36 that add to -12:
• ​-6 * -6 = 36
• -6 + -6 = -12
• Answer: (x - 6)(x - 6) OR (x - 6)2
3. Factorize x2 + 8x - 20
• Factors of -20 that add to 8:
• 10 * -2 = -20
• 10 + -2 = 10 - 2 = 8
• Answer: (x + 10)(x - 2) OR (x - 2)(x + 10)

## Type 2 Edit

(Where the coefficient of x2 is a common factor)

Method

1. Factorise by having the common factor outside the bracket and a quadratic expression inside the bracket