The owner of a candy store is creating a candy medley that costs $2.45 per kilogram. The medley contains jelly beans at $3.25 per kilogram, plus gumdrops at $1.25 per kilogram. If
there are 9 kilograms of jelly beans available, how many kilograms of gumdrops will the
owner need to use?
Write your answer as a whole number or as a decimal rounded to the nearest tenth.
kilograms

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

just sum

10 + 10 = 20

the first one is x^2+2x+2

the second one is x^2+4

the last one is x^2-4x+8