Unlock Algebraic Mysteries: Solving For 'g'

by Alex Johnson 44 views

When faced with an algebraic equation, it's natural to wonder about the specific values of variables that will make the entire statement true. In this case, we're presented with the equation (x+7)(x−4)=x2+9x−28(x+7)(x-4)=x^2+9x-28. While the equation is already presented in a seemingly solved form, the core question is to determine if there's a specific value for a variable, let's assume it's represented by 'gg' in a broader context or perhaps it's a typo and should be related to the coefficients or constants within the given equation. Often, these types of problems are designed to test your understanding of algebraic manipulation and the fundamental properties of equations. Let's break down the equation and explore how to approach this.

Understanding the Equation

The equation (x+7)(x−4)=x2+9x−28(x+7)(x-4)=x^2+9x-28 involves two sides. The left side is a product of two binomials, (x+7)(x+7) and (x−4)(x-4). The right side is a quadratic trinomial, x2+9x−28x^2+9x-28. To determine if the equation holds true for all values of xx, or if there's a specific condition to be met, we need to expand the left side and compare it to the right side.

We can expand the left side using the distributive property, often remembered by the acronym FOIL (First, Outer, Inner, Last):

  • First: x∗x=x2x * x = x^2
  • Outer: x∗(−4)=−4xx * (-4) = -4x
  • Inner: 7∗x=7x7 * x = 7x
  • Last: 7∗(−4)=−287 * (-4) = -28

Combining these terms, we get: x2−4x+7x−28x^2 - 4x + 7x - 28.

Now, we simplify this expression by combining the like terms (the xx terms):

x2+(−4x+7x)−28=x2+3x−28x^2 + (-4x + 7x) - 28 = x^2 + 3x - 28.

So, the expanded form of the left side of the equation is x2+3x−28x^2 + 3x - 28.

Now, let's compare this to the right side of the original equation, which is x2+9x−28x^2 + 9x - 28.

Our expanded left side is x2+3x−28x^2 + 3x - 28, and the given right side is x2+9x−28x^2 + 9x - 28.

For the equation (x+7)(x−4)=x2+9x−28(x+7)(x-4)=x^2+9x-28 to be true, the expanded left side must equal the right side: x2+3x−28=x2+9x−28x^2 + 3x - 28 = x^2 + 9x - 28.

Identifying the Discrepancy

Let's analyze the equation x2+3x−28=x2+9x−28x^2 + 3x - 28 = x^2 + 9x - 28.

We can see that the x2x^2 terms are identical on both sides, and the constant terms (-28) are also identical. The only difference lies in the coefficient of the xx term. On the left side, it's +3x+3x, and on the right side, it's +9x+9x.

To solve for xx (if that were the goal, but our problem is about finding 'gg'), we would subtract x2x^2 from both sides:

3x−28=9x−283x - 28 = 9x - 28.

Then, we would add 28 to both sides:

3x=9x3x = 9x.

Finally, we would subtract 3x3x from both sides:

0=6x0 = 6x.

Dividing by 6, we get x=0x=0.

This means that the original equation (x+7)(x−4)=x2+9x−28(x+7)(x-4)=x^2+9x-28 is only true when x=0x=0. However, the question asks for the value of 'gg' that makes the equation true. This suggests that 'gg' is not a variable like xx that we solve for within the structure of the equation as presented. Instead, 'gg' likely represents a missing constant or coefficient that, if correctly identified, would make the equation an identity (true for all xx) or would represent a specific condition.

Reinterpreting the Question: What is 'gg'?

Given the standard format of algebraic problems, it's highly probable that the question intends to imply that the equation should be true, and the value of 'gg' is what's missing or incorrect. If the problem intended for the equation to be an identity (true for all values of xx), then the coefficients on both sides must match.

Let's assume the equation was meant to be (x+7)(x−4)=x2+gx−28(x+7)(x-4)=x^2+gx-28. In this hypothetical scenario, we would expand the left side: x2+3x−28x^2 + 3x - 28. For this to equal x2+gx−28x^2+gx-28, the coefficient of the xx term must match. Therefore, gg would have to be 3.

Alternatively, if the equation was presented as (x+a)(x+b)=x2+9x−28(x+a)(x+b)=x^2+9x-28, we would be looking for factors of -28 that add up to 9. These numbers are 11.61 and -2.61, not integer values. If the factors were (x+7)(x+7) and (x+g)(x+g), then (x+7)(x+g)=x2+gx+7x+7g=x2+(g+7)x+7g(x+7)(x+g) = x^2 + gx + 7x + 7g = x^2 + (g+7)x + 7g. For this to equal x2+9x−28x^2+9x-28, we would need:

  1. g+7=9ightarrowg=2g+7 = 9 ightarrow g = 2
  2. 7g=−28ightarrowg=−47g = -28 ightarrow g = -4

These two conditions for gg contradict each other (g=2g=2 and g=−4g=-4), indicating that the original premise of (x+7)(x+g)=x2+9x−28(x+7)(x+g)=x^2+9x-28 is not consistent with the structure of the problem if we assume the problem implies a correct and consistent algebraic identity.

Let's return to the exact wording: "What value of gg makes the equation true? (x+7)(x−4)=x2+9x−28(x+7)(x-4)=x^2+9 x-28"

The most straightforward interpretation is that the 'gg' is part of the original equation, but it was written as a '9' in the question. It's a common scenario in math problems that a variable is intended but a number is written instead, or vice-versa. If we assume that the '99' in x2+9x−28x^2+9x-28 was meant to be 'gg', then the equation would be (x+7)(x−4)=x2+gx−28(x+7)(x-4)=x^2+gx-28.

As we calculated earlier, expanding (x+7)(x−4)(x+7)(x-4) yields x2+3x−28x^2 + 3x - 28.

For this to be equal to x2+gx−28x^2+gx-28, we must equate the coefficients of the xx term:

3x=gx3x = gx

This implies g=3g=3.

Conclusion: The Value of 'gg'

Based on the standard conventions of algebraic problem-solving and the given structure, the most logical conclusion is that the digit '9' in the equation (x+7)(x−4)=x2+9x−28(x+7)(x-4)=x^2+9x-28 was intended to be the variable 'gg'. Thus, the equation was meant to be written as (x+7)(x−4)=x2+gx−28(x+7)(x-4)=x^2+gx-28.

When we expand the left side, (x+7)(x−4)(x+7)(x-4), we perform the multiplication:

ximesx=x2x imes x = x^2 ximes−4=−4xx imes -4 = -4x 7imesx=7x7 imes x = 7x 7imes−4=−287 imes -4 = -28

Combining these terms gives us x2−4x+7x−28x^2 - 4x + 7x - 28, which simplifies to x2+3x−28x^2 + 3x - 28.

Now, we set this equal to the right side of the intended equation: x2+3x−28=x2+gx−28x^2 + 3x - 28 = x^2 + gx - 28.

To make this equation true for all values of xx, the coefficients of corresponding terms must be equal. The x2x^2 terms match, and the constant terms (-28) match. Therefore, the coefficients of the xx terms must also match:

3x=gx3x = gx

This implies that g=3g=3.

So, the value of gg that makes the equation (x+7)(x−4)=x2+gx−28(x+7)(x-4)=x^2+gx-28 true is 33.

If the question is strictly interpreted as