Recognize expression type: Recognize the type of expression we are dealing with.The expression 64x2−144x+81 is a quadratic expression in the form ax2+bx+c. We will attempt to factor it as a perfect square trinomial, which has the form (ax+b)2.
Check for perfect square trinomial: Check if the expression is a perfect square trinomial.For an expression to be a perfect square trinomial, the first and last terms must be perfect squares, and the middle term must be twice the product of the square roots of the first and last terms.64x2 is a perfect square (8x)2, and 81 is a perfect square (9)2. The middle term, −144x, should be equal to 2×(8x)×(9) if the expression is a perfect square trinomial.
Verify middle term: Verify the middle term.Calculate 2×(8x)×(9) to see if it equals −144x.2×(8x)×(9)=144xHowever, we need −144x, so the middle term matches the requirement for a perfect square trinomial.
Write factored form: Write the factored form of the expression.Since the expression is a perfect square trinomial, it can be factored as (ax+b)2, where ax is the square root of the first term and b is the square root of the last term, with the sign of the middle term.The factored form is (8x−9)2.
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