### Instruction: Factor $7x^3 - 21x^2 + 14x$.### Response: I notice that all the terms in the expression have a common factor of 7x, so I can factor that out first.
That gives me $7x(x^2 - 3x + 2)$.
Now I want to factor the quadratic expression inside the parentheses.
I look for two numbers that multiply to 2 and add to -3.
I see that -1 and -2 work.
So I can write $x^2 - 3x + 2$ as $(x - 1)(x - 2)$.
Therefore, the final factored form is $7x(x - 1)(x - 2)$.