Answer:
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Step-by-step explanation:
We have the following expression:
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We can find the GCF with the following steps.
1. Find the GCF for the numerical part 15 and -21
The factors for 15 are : 1,3,5,15
The factors for -21 are -21,-7,-3,-1,1,3,7,21
And the common factors are 1,3
The GCF for the numerical part is 3*1 = 3
2. Find the GCF for the variable
The factors of x^2 are : x*x
The factors of x are: x
The common factors are x for this case, so then the GCF for the variable part is x
3. Multiply the two results from steps 1 and 2
GCf= 3*x = 3x
If we consider the new expression:
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We can find the GCF with the following steps.
1. Find the GCF for the numerical part 15 and -21
The factors for 15 are : 1,3,5,15
The factors for -21 are 1,3,7,21
And the common factors are 1,3
The GCF for the numerical part is 3*1 = 3
2. Find the GCF for the variable
The factors of x^2 are : x*x
The factors of x are: x
The common factors are x for this case, so then the GCF for the variable part is x
3. Multiply the two results from steps 1 and 2
GCf= 3*x = 3x
And as we can see both GCF are equal. So then we satisfy the condition required.