Elvin has 90 comic books he donates a third to a library then he buys 4 comic books at each at 7 bookstores how many comics do he have afterwards writes an expression to represent the number of books he buys

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

the photograph is photographer and- in the process- ourselves.

step-by-step explanation:

wait nvm i know the correct answer now its 100%   81 square feet

~batmans wife dun dun

wth is with the little mtn top and what are you talking about like fix your words and accually make sence with them and i like was in a completly different question like three times like it seems like your ilitteret