What is the radius of the circle whose equation is x2 + y2 = 9?
81
3
9

3

Step-by-step explanation:

x^2 + y^2 = 9

The equation of a circle is

(x-h)^2 + (y-k)^2 = r^2

( h,k) is the center and r is the radius

x^2 + y^2 = 3^2

The radius is 3

1e+27

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