Determine factoring technique: Determine the appropriate factoring technique for 25r2−16. Since we have a difference of squares, we can use the formula a2−b2=(a−b)(a+b).
Identify perfect squares: Identify the terms in the expression 25r2−16 as perfect squares.25r2 can be written as (5r)2 because 5r×5r=25r2.16 can be written as 42 because 4×4=16.So, 25r2−16 is in the form of a2−b2 where a=5r and 25r20.
Apply difference of squares formula: Apply the difference of squares formula to factor the expression.Using a=5r and b=4, we get:(5r)2−42=(5r−4)(5r+4).
Write factored form: Write down the factored form of the expression.The factored form of 25r2−16 is (5r−4)(5r+4).
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