Use the following system of equations to select the appropriate response. Step 1 of the substitution Method to solve system of equations. use the second equation and solve for the x Variable.
A. x = y - 3
B. x = -y + 3
C. x = -y - 3
D. x = y + 3

Step-by-step explanation:

Given system of equations is,

8x + 10y = 120 -----(1)

x - y = -3 ------(2)

From the second equation,

x = y - 3 [Option A]

Now we substitute the value of x in equation (1) and solve for y,

8(y - 3) + 10y = 120

8y - 24 + 10y = 120

18y = 120 - 24

y = = 8

From equation (2)

x - 8 = -3

x = 8 - 3

x = 5

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