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Ch. R - Algebra Review
Lial - Trigonometry 12th Edition
Lial12th EditionTrigonometryISBN: 9780136552161Not the one you use?Change textbook
Chapter 1, Problem 77

Factor each polynomial completely. See Example 6. 4x² - 28x + 40

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1
First, identify the greatest common factor (GCF) of all the terms in the polynomial \$4x^{2} - 28x + 40$. The GCF is the largest number that divides each coefficient evenly.
Factor out the GCF from the polynomial. This means rewriting the polynomial as \$4(x^{2} - 7x + 10)$.
Next, focus on factoring the quadratic inside the parentheses: \(x^{2} - 7x + 10\). Look for two numbers that multiply to \(10\) (the constant term) and add up to \(-7\) (the coefficient of \(x\)).
Write the quadratic as a product of two binomials using the two numbers found: \((x - a)(x - b)\), where \(a\) and \(b\) are the numbers from the previous step.
Finally, write the completely factored form by combining the GCF and the factored quadratic: \$4(x - a)(x - b)$.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Factoring Quadratic Polynomials

Factoring quadratic polynomials involves expressing a quadratic expression in the form ax² + bx + c as a product of two binomials. This process helps simplify expressions and solve equations by finding the roots of the polynomial.
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