R(x) = (60x +6x)(12- 0.5x)
"Find how many people should attend the rink for the revenue to be maximum"
you didn't tell us what R or x means. so I'll assume you want to solve for R in terms of x.
R(x) = (60x +6x)(12+ -0.5x)
R(x) = 60x*12 + 60x*-0.5x + 6x*12 + 6x*-0.5x
R(x) = 720x + -30x^2 + 72x + -3x^2
R(x) = 792x - 33x^2
R(x) = (72)(11)(x) - (3)(11)(x)(x)
R(x) = (11)(x) (72 - 3x)
R(x)/x = (11)(x) (72 - 3x)/x
R= 11(72-3x)
R=792-33x
I believe that's right, but tell me if I made a mistake anywhere
Comments
you didn't tell us what R or x means. so I'll assume you want to solve for R in terms of x.
R(x) = (60x +6x)(12- 0.5x)
R(x) = (60x +6x)(12+ -0.5x)
R(x) = 60x*12 + 60x*-0.5x + 6x*12 + 6x*-0.5x
R(x) = 720x + -30x^2 + 72x + -3x^2
R(x) = 792x - 33x^2
R(x) = (72)(11)(x) - (3)(11)(x)(x)
R(x) = (11)(x) (72 - 3x)
R(x)/x = (11)(x) (72 - 3x)/x
R= 11(72-3x)
R=792-33x
I believe that's right, but tell me if I made a mistake anywhere