Look at the student work shown below. simplify: 4t(2s – 7). (4t)(2s) – 7 8st - 7 did the student correctly simplify the expression? if “yes,” explain the steps the student followed. if “no,” explain what the student did wrong and what should have been done.

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