How can you decide which variable to solve for the first when you are solving a linear system by substitution

The variable having largest coefficient is solved first.

Step-by-step explanation:

The variable having greater coefficient is solved first because we can substitute the value of smaller coefficient variable easily as compared to the greater one.

Because in substitution method we first substitute the value of coefficient which has smallest coefficient and as a result the coefficient with greater coefficient is solved.

its not b

step-by-step explanation:

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