Finding the Difference: (y^2 - 4y + 9) - (3y^2 - 6y - 9)
This problem asks us to find the difference between two polynomials. Here's how to solve it step-by-step:
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Distribute the negative sign: The minus sign in front of the second set of parentheses means we need to multiply each term inside the parentheses by -1.
This gives us: (y^2 - 4y + 9) + (-1 * 3y^2) + (-1 * -6y) + (-1 * -9)
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Simplify: Now, simplify the expression by multiplying the -1:
y^2 - 4y + 9 - 3y^2 + 6y + 9
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Combine like terms: Combine the terms with the same variable and exponent:
(y^2 - 3y^2) + (-4y + 6y) + (9 + 9)
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Final Result: Add the coefficients of the like terms:
-2y^2 + 2y + 18
Therefore, the difference between the two polynomials (y^2 - 4y + 9) and (3y^2 - 6y - 9) is -2y^2 + 2y + 18.