Answer:
The difference is 1.97 ounces.
Step-by-step explanation:
4.82-2.85= 1.97
![\bf (y-k)=a(x-h)^2\qquad \begin{cases} vertex\ (h,k)\\ vertex\ (-4,2) \end{cases}\\\\\\ y-2=a(x-(-4))^2 \implies y=a(x+4)^2+2](https://tex.z-dn.net/?f=%5Cbf%20%28y-k%29%3Da%28x-h%29%5E2%5Cqquad%20%0A%5Cbegin%7Bcases%7D%0Avertex%5C%20%28h%2Ck%29%5C%5C%0Avertex%5C%20%28-4%2C2%29%0A%5Cend%7Bcases%7D%5C%5C%5C%5C%5C%5C%20y-2%3Da%28x-%28-4%29%29%5E2%0A%5Cimplies%0Ay%3Da%28x%2B4%29%5E2%2B2)
so.. what is the coefficient "a"?
well
now, we know, another point on the graph, besides the vertex, we know a y-intercept, that is, 0, -30, that simply means when x = 0, y = -30
![\bf y=a(x+4)^2+2\qquad (0,-30)\implies -30=a(0+4)^2+2 \\\\\\ -30-2=a4^2\implies \cfrac{-32}{16}=a\implies -2=a \\\\\\ thus\implies y=-2(x+4)^2+2](https://tex.z-dn.net/?f=%5Cbf%20y%3Da%28x%2B4%29%5E2%2B2%5Cqquad%20%280%2C-30%29%5Cimplies%20-30%3Da%280%2B4%29%5E2%2B2%0A%5C%5C%5C%5C%5C%5C%0A-30-2%3Da4%5E2%5Cimplies%20%5Ccfrac%7B-32%7D%7B16%7D%3Da%5Cimplies%20-2%3Da%0A%5C%5C%5C%5C%5C%5C%0Athus%5Cimplies%20y%3D-2%28x%2B4%29%5E2%2B2)
now, getting the x-intercepts, is just the zeros, or solution to the quadratic
![\bf y=-2(x+4)^2+2\impliedby \textit{setting y to 0} \\\\\\ 0=-2(x+4)^2+2\implies -2=-2(x+4)^2\implies \cfrac{-2}{-2}=(x+4)^2 \\\\\\ 1=(x+4)^2\implies \pm\sqrt{1}=x+4\implies \pm 1-4 = x\to \begin{cases} (-3\ ,\ 0)\\ (-5\ ,\ 0) \end{cases}](https://tex.z-dn.net/?f=%5Cbf%20y%3D-2%28x%2B4%29%5E2%2B2%5Cimpliedby%20%5Ctextit%7Bsetting%20y%20to%200%7D%0A%5C%5C%5C%5C%5C%5C%0A0%3D-2%28x%2B4%29%5E2%2B2%5Cimplies%20-2%3D-2%28x%2B4%29%5E2%5Cimplies%20%5Ccfrac%7B-2%7D%7B-2%7D%3D%28x%2B4%29%5E2%0A%5C%5C%5C%5C%5C%5C%0A1%3D%28x%2B4%29%5E2%5Cimplies%20%5Cpm%5Csqrt%7B1%7D%3Dx%2B4%5Cimplies%20%5Cpm%201-4%20%3D%20x%5Cto%20%0A%5Cbegin%7Bcases%7D%0A%28-3%5C%20%2C%5C%200%29%5C%5C%0A%28-5%5C%20%2C%5C%200%29%0A%5Cend%7Bcases%7D)
notice, "y" is 0 on both cases, because, is an x-intercept, or a zero, and when the graph touches the x-axis, "y" is zero
The Mississippi River Basin should be the correct answer.
Sorry, But no. I hope you figure it out :)
Example case:
![\begin{cases}x+y=1\\2x+2y=2\end{cases}](https://tex.z-dn.net/?f=%5Cbegin%7Bcases%7Dx%2By%3D1%5C%5C2x%2B2y%3D2%5Cend%7Bcases%7D)
The second equation is twice the first, so subtracting that from the second equation yields the identity 0 = 0.
This is an identity. It's an equation that holds true (clearly, 0 is the same as 0) regardless of the values of the variables, which means any pair of numbers
![(x,y)](https://tex.z-dn.net/?f=%28x%2Cy%29)
is a solution to the system.