Respuesta :
They should sell each yearbook 5 dollars cheaper because they will make 4,500 dollars more if they did that. With the discount and extra yearboos they will earn $29,250.
Answer:
$35 per yearbook; $30,625
Step-by-step explanation:
In this function, x represents the number of $5 decreases. To find the vertex, we first find the axis of symmetry. We will first write this function in standard form, by multiplying:
R(x) = (500+125x)(50-5x)
= 500(50)+500(-5x)+125x(50)+125x(-5x)
= 25000+-2500x+6250x-625x²
= 25000+3750x-625x²
= -625x²+3750x+25000
The axis of symmetry is found using the formula
x = -b/2a
x = -3750/2(-625) = -3750/(-1250) = 3
Next we use this value of x to find the y-coordinate of the vertex. We substitute this into the function:
R(3) = -625(3²)+3750(3)+25000
= -5265+11250+25000 = 30625
This makes the vertex (3, 30625). This means with 3 $5 decreases, the revenue will be $30,625.
3 $5 decreases means decreasing 3(5) = $15 from the price. This means they sell the yearbooks for 50-15 = $35.