Question

Martin has a gift card to a coffee shop. Each day he buys the same coffee. This table shows the amount remaining in dollars on the gift card on different days. Time (days) 2 4 5 7 Amount remaining ($) $24.10 $18.20 $15.25 $9.35
Which equation represents this situation, where x is the time and y is the amount remaining?
A) y+15.25=−2.95(x+5)
B) y+24.10=2.95(x−2)
C) y−9.35=−2.95(x−7)
D) y−18.20=−2.95(x+4)

Answer 1

Answer:

$y-9.35=-2.95(x-7)$

Step-by-step explanation:

Time (days)                      2         4                 5        7

Amount remaining ($) $24.10    $18.20    $15.25    $9.35

We are supposed to find  equation represents this situation, where x is the time and y is the amount remaining

So, we will use point slope form :

Formula : $y-y_1=m{x_2-x_1}(x-x_1)$

Where $m = \frac{y_2-y_1}{x_2-x_1}$

$(x_1,y_1)=(2,24.10)$

$(x_2,y_2)=(4,18.20)$

$m = \frac{18.20-24.110}{4-2}$

$m =-2.95$

Now (x_1,y_1)=(7,9.35)

Formula : $y-y_1=m(x-x_1)$

Substitute the values:

$y-9.35=-2.95(x-7)$

So, Option c is true

Hence equation represents this situation, where x is the time and y is the amount remaining is $y-9.35=-2.95(x-7)$

Answer 2

Answer:

The answer is C. y – 9.35 = −2.95(x – 7).

Step-by-step explanation: