Question

The frequency of a voice is given by the equation: y = 12x + 13, where y = amplitude of sound and x = time period.

Which of the following graph represents the equation for the voice frequency?

• A.
• B. Cannot be determined
• C.
• D.

Answer 1

The correct option is A

Let's analyze the given equation:

$y=12x+13$

$\text{At}x=1,y=12\left(1\right)+13=12+13=25$

$\text{At}x=2,y=12\left(2\right)+13=24+13=37$

$\text{At}x=3,y=12\left(3\right)+13=36+13=49$

With increase in the value of x, the value of y is also increasing.

Therefore, we can say that equation has a positive constant of proportionality and matches with the graph given below.