Answer:

Step-by-step explanation:
we know that
A relationship between two variables, x, and y, represent a proportional variation if it can be expressed in the form
or
In a proportional relationship the constant of proportionality k is equal to the slope m of the line and the line passes through the origin
In this problem we have

Substitute the values and solve for k


therefore
the equation of the line is equal to

we have

where
c---------> is the total cost of going to the carnival
t---------> is the number of
tickets purchased
we know that
<u>the domain of the function is the interva</u>l---------------> [0,∞)
Because the number of tickets can not be negative
<u>The range of the function is the interval</u>-------------> [10,∞)
Because the total cost can not be negative
using a graph tool
see the attached figure
The answer in the attached figure
We can factor by grouping. To do so, we multiply the leading coefficient with the constant at the end. In other words, a times c (ax^2 + bx + c).
15*-4 = -60
Now we need to split the b term into two pieces that multiply to -60 and add to 4.
-6 and 10 will work.
Now group one part of b with the 15x^2 and the other part with -4.
(15x^2 + 10x) + (-6x - 4)
Now factor both terms.
5x(3x+2) - 2(3x+2)
3x+2 is one of our factors and 5x-2 is the other.
(3x+2)(5x-2)=0
Now just find the zeros.
3x+2 = 0
3x = -2
x = -2/3
And
5x-2 = 0
5x = 2
x = 2/5
So the answer is x = -2/3 and x = 2/5
The answer is B. Thank you