High School

Select the correct answer.

The product of two integers is [tex]$112$[/tex]. One number is four more than three times the other. Which of the following equations could be used to find one of the numbers?

A. [tex]$3x^2 + 4x = 112$[/tex]
B. [tex]$3x^2 + 4 = 112$[/tex]
C. [tex]$4x^2 + 3x = 112$[/tex]
D. [tex]$4x^2 + 3 = 112$[/tex]

Answer :

Let's solve the problem step by step.

We need to find an equation that could be used to find one of the numbers, given that the product of two integers is [tex]\(112\)[/tex], and one number is four more than three times the other.

Let's denote the two unknown integers as [tex]\(x\)[/tex] and [tex]\(y\)[/tex]. We're given two conditions:
1. The product of the integers is 112.
2. One number is four more than three times the other.

#### Step 1: Express the Given Conditions

1. The product of the integers:
[tex]\[
x \cdot y = 112
\][/tex]

2. One number is four more than three times the other. Let's assume that [tex]\(x\)[/tex] is four more than three times [tex]\(y\)[/tex]:
[tex]\[
x = 3y + 4
\][/tex]

#### Step 2: Substitute the Second Condition into the First

We can substitute [tex]\(x\)[/tex] from the second condition into the first condition:
[tex]\[
(3y + 4) \cdot y = 112
\][/tex]

#### Step 3: Simplify the Equation

Now, let's simplify this equation:
[tex]\[
3y^2 + 4y = 112
\][/tex]

#### Step 4: Rearrange to Match the Standard Form of a Quadratic Equation

We need to put this equation in the standard quadratic form [tex]\(ax^2 + bx + c = 0\)[/tex]:
[tex]\[
3y^2 + 4y - 112 = 0
\][/tex]

#### Step 5: Identify the Correct Equation

The simplified equation [tex]\(3y^2 + 4y - 112 = 0\)[/tex] matches one of the given options with the correct structure. We can identify that the correct option is:

[tex]\[
\text{A. } 3x^2 + 4x = 112
\][/tex]

Therefore, the equation that could be used to find one of the numbers is:
[tex]\[
\boxed{3x^2 + 4x = 112}
\][/tex]

Option A is the correct answer.