Problem 30 - College Algebra

Question

Factor each trinomial, or state that the trinomial is prime. $$ 8 x^{2}+33 x+4 $$

Step-by-Step Solution

Answer

The factored form of the given trinomial is \(x(4x + 1) (2x + 4)\).

Step 1: Identify the Coefficients

Identify the coefficients of the trinomial. Here, \(a = 8\), \(b = 33\), and \(c = 4\).

Step 2: Apply the Factoring Formula

To factor a trinomial of the form \(ax^2 + bx + c\), find two numbers that multiply to \(ac\) (which is 32 in this case) and add up to \(b\). The numbers that satisfy these conditions are \(4\) and \(8\).

Step 3: Apply the Factorization

Apply the factorization by placing \(4\) and \(8\) in the binomial expression. The factored form of the trinomial is \(x(4x + 1) (2x + 4)\).

Key Concepts

Polynomial Factorization

Factorization is a way of breaking down complex mathematical expressions into simpler parts. When it comes to polynomial factorization, we are typically dealing with expressions that involve terms raised to the power of a variable, like quadratic trinomials. Think of factoring polynomials as unraveling a piece of knitted fabric back into its individual threads.

To factor a polynomial, especially a trinomial, we look for two numbers that have a specific relationship with the coefficients of the polynomial. The coefficients are the numbers that appear in front of the variables. In the case of a trinomial in the form of \(ax^2 + bx + c\), the process hinges on finding two numbers that multiply to \(a \times c\) and add to \(b\).

Here's an easy analogy: imagine you have a certain amount of money \(ac\) in your account and you want to divide it into two investments that altogether bring you \(b\) amount of profit. The challenge is to find those two amounts; similarly, in polynomials, the two numbers are like those investments which are crucial for factorization.

Trinomial Coefficients

In algebra, coefficients are like tags that specify the quantity of something. For the trinomial coefficients, we're looking at three specific tags for the terms in the expression \(ax^2 + bx + c\). The 'a' is the coefficient of the squared term, 'b' is the coefficient of the 'x' term, and 'c' is the constant coefficient. These coefficients are vital clues in solving the puzzle of factorization.

Consider them as the DNA of the trinomial; they give you all the necessary information about how to split the trinomial into simpler factors. In the example of \(8x^2 + 33x + 4\), the coefficients are the signposts that guide us to find the numbers 4 and 8, which then allow us to break the trinomial into two binomials that are its factors.

Algebraic Expressions

The wide world of algebra is home to these special phrases known as algebraic expressions. They're a mix of numbers, variables (like 'x' or 'y'), and operation signs (plus, minus, times, divided by). In simple terms, algebraic expressions are like sentences in the language of mathematics.

An algebraic expression provides a way to represent a variety of real-world scenarios mathematically. A trinomial is one type of algebraic expression that resembles a small 'sentence' made up of three terms. For example, \(8x^2 + 33x + 4\) tells a story where 'x' is a character whose impact changes depending on its role (squared, or just by itself). Factoring breaks down this expressive structure into simpler chunks - the phrases that better reveal the interactions of the characters involved.