Welcome to Westonci.ca, where your questions are met with accurate answers from a community of experts and enthusiasts. Discover solutions to your questions from experienced professionals across multiple fields on our comprehensive Q&A platform. Our platform provides a seamless experience for finding reliable answers from a network of experienced professionals.

A direct variation function contains the points (2, 14) and (4, 28). Which equation represents the function?

A. [tex]\( y = \frac{x}{14} \)[/tex]
B. [tex]\( y = \frac{x}{7} \)[/tex]
C. [tex]\( y = 7x \)[/tex]
D. [tex]\( y = 14x \)[/tex]


Sagot :

To find the equation that represents the direct variation function containing the points [tex]\((2, 14)\)[/tex] and [tex]\((4, 28)\)[/tex], follow these steps:

1. Identify the general form of the direct variation equation:
[tex]\[ y = kx \][/tex]
where [tex]\( k \)[/tex] is the constant of proportionality.

2. Find the constant of proportionality [tex]\( k \)[/tex] using the provided points:
Given the points [tex]\((2, 14)\)[/tex] and [tex]\((4, 28)\)[/tex], we know that:
[tex]\[ y_1 = 14 \quad \text{when} \quad x_1 = 2 \][/tex]
and
[tex]\[ y_2 = 28 \quad \text{when} \quad x_2 = 4 \][/tex]

3. Calculate the slope (constant of proportionality) [tex]\( k \)[/tex]:
The slope [tex]\( k \)[/tex] of the line passing through the points [tex]\((x_1, y_1)\)[/tex] and [tex]\((x_2, y_2)\)[/tex] in direct variation can be found using the formula:
[tex]\[ k = \frac{y_2 - y_1}{x_2 - x_1} \][/tex]

4. Substitute the given points into the formula:
[tex]\[ k = \frac{28 - 14}{4 - 2} \][/tex]

5. Perform the arithmetic operations:
[tex]\[ k = \frac{14}{2} \][/tex]
[tex]\[ k = 7 \][/tex]

6. Form the direct variation equation with the calculated [tex]\( k \)[/tex]:
Substitute [tex]\( k = 7 \)[/tex] into the general form of the equation:
[tex]\[ y = 7x \][/tex]

Therefore, the equation that represents the direct variation function is:
[tex]\[ y = 14x \][/tex]

From the provided options, the correct one is:
[tex]\[ y = 14x \][/tex]
So, the answer is:
[tex]\[ \boxed{4} \][/tex]