Martin has a gift card to a coffee shop. Each day he buys the same coffee. The table shows the amount remaining on the gift card on different days.

Which equation represents the situation?

Martin’s Gift Card
Days
2 4 5 7
Amount remaining 24.10 18.20 15.25 9.35


A.
y – 9.35 = −2.95(x – 7)

B.
y – 18.20 = 2.95(x + 4)

C.
y + 15.25 = −2.95(x + 5)

D.
y + 24.10 = 2.95(x – 2)

Respuesta :

Your answer would be A. y – 9.35 = −2.95(x – 7).

We want to see which linear equation represents the amount remaining on the gift card. We will see that the correct option is A:

y – 9.35 = −2.95(x – 7)

A linear equation in the point-slope form is written as:

y - y₁ = a*(x - x₁)

Where a is the slope of the line and (x₁, y₁) is a point on the line.

If we know two points on the line, (x₁, y₁)  and (x₂, y₂) then we can write the slope as:

[tex]a = \frac{y_2 - y_1}{x_2 - x_1}[/tex]

Here we can use the two first points:

(2, 24.10)

(4, 18.20)

Then the slope is:

[tex]a = \frac{18.20 - 24.10}{4 - 2} = -2.95[/tex]

Then the equation is something like:

y - y₁ = -2.95*(x - x₁)

Now, from the given options the only one where (x₁, y₁) is a point on the line is the first option, where:

x₁ = 7

y₁ = 9.35

So the correct option is A:

y – 9.35 = −2.95*(x – 7)

If you want to learn more, you can read:

https://brainly.com/question/11897796

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