For the data in the table, does y vary directly with x? if it does, write an equation for the direct variation.

Look at pictures below to understand how I got my answer.

Step-by-step explanation:

no; this is not direct variation

Step-by-step explanation:

y = kx is the formula for direct variation

For the first line

28 = k*4

Divide each side by 4

28/4 = 4k/4

7 = k

Now our equation is y = 7x

Substitute the second line

48 = 7*6

48 = 42

This is not true, so this cannot be direct variation

fist on the left goes with the third on the right. second on the left goes with the fourth on the right. third on the left goes with the second on the right. the fourth on the left goes with first on the right

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