Identify GCF of terms: Identify the greatest common factor (GCF) of the terms in the expression 5x2−320.The GCF of 5x2 and 320 is 5.
Factor out GCF: Factor out the GCF from the expression. 5x2−320=5(x2−64)
Recognize difference of squares: Recognize that the expression inside the parentheses is a difference of squares. x2−64 can be written as x2−82, which is in the form a2−b2.
Apply difference of squares formula: Apply the difference of squares formula to factor the expression inside the parentheses.The difference of squares formula is a2−b2=(a−b)(a+b).So, x2−82=(x−8)(x+8).
Write fully factored form: Write the fully factored form of the original expression by including the GCF.5x2−320=5(x−8)(x+8)
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