Identify common factor: Identify a common factor in the terms 3x2 and −147.Both terms are divisible by 3.
Factor out GCF: Factor out the greatest common factor (GCF) from the expression.GCF of 3x2 and −147 is 3.3x2−147=3(x2−49)
Recognize difference of squares: Recognize that x2−49 is a difference of squares.x2=x×x=(x)249=7×7=72So, x2−49=(x)2−72
Use difference of squares formula: Use the difference of squares formula to factor x2−49.The difference of squares formula is a2−b2=(a−b)(a+b).(x)2−72=(x−7)(x+7)
Combine factored form with GCF: Combine the factored form of x2−49 with the GCF that was factored out.3(x2−49)=3(x−7)(x+7)
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