Question

please help, need answer fast!
The graph shows the daily revenue earned selling coupon cards in a fundraiser if the price is decreased by x dollars.


Which function can be used to determine the daily revenue if the price of a coupon card is decreased by x dollars?

Answer 1

From given graph we see that points forms a parabolic shape that means we can use quadratic model to find the equation whose formula is given by:

$y=a(x-h)^2+k$

where (h,k) represents vertex.

From graph we see that vertex is (3,49).

Hence h=3 and k=49

Plug these values into above formula

we get:

$y=a(x-3)^2+49$

Now we need to find the value of a, so we can plug any point say (5,45) then we get:

$45=a(5-3)^2+49$

$45=a(2)^2+49$

$45=4a+49$

$45-49=4a$

$-4=4a$

$-1=a$

Plug value of a, h and k into above formula, we get:

$y=-1(x-3)^2+49$

$y=-1(x^2-6x+9)+49$

$y=-x^2+6x-9+49$

$y=-x^2+6x+40$

which best matches with first choice

Hence final answer is $R(x)=-x^2+6x+40$

Answer 2

Answer:A on edge:)

Step-by-step explanation: