Answer: $37.20
Step-by-step explanation:
Just add those 2 amounts together
Eight *(a number) plus 5*(another number) is -13.
translates to:
8(x) + 5(y) = -13
The sum of (the number) and (the other number) is 1.
translates to:
(x) + (y) = 1
We have a system of two equations involving two unknowns: x and y.

We can easily solve the system using Substitution or Elimination. Let's use Elimination this time.
We'll multiply the second equation by -8 so that the x's match up.

When we add the equations together, the x's will fall out of the equation, summing to zero. The 5y and -8y will sum to -3y and the right hand side will sum to -21.

Divide by -3,

Plug back into one of your original equations to find the value of x,

Subtract 7,
Well I would solve it but where's the problem?
You get (2x+3)(4x^2-6x+9) when you factor 8x^3+27=0. You just divide by 3 to simplify it.
The answer is 64x^2+114x+81. Hope this helps.