Suppose that the function f(x)=3x+10 represents the cost to rent a movie for a month. Kim has $15. How many more dollars does she need to rent 8 movies?

$19

Step-by-step explanation:

Given data

Cost of movie

f(x)=3x+10

Hence the cost of 8 movies is

f(x)=3(8)+10

f(x)=24+10

f(x)=$34

Hence the cost of 8 movies is $34, Kim needs extra

=34-15

=$19

answer: 204

step-by-step explanation:

we are told that the revenue is

x⋅(4080−10x)=−10x^2+4080x

this is a quadratic function, so to maximize it we should find the x-value of its vertex. recall that the x-value of the vertex of the parabola ax^2+bx+c is given by the formula −b/2a.

so in this case, we have a=−10 and b=4080, so the x-value of the vertex is

−b/2a= −(4080)/2(−10)=204