so I think it’s D) $549.68.
I added $824.52 and $824.52 since they’re going there and back. the question also said they’re going to split the cost equally so I divided by 3 after adding. And I got $549.68
Check the picture below.
![\bf A=\cfrac{h(a+b)}{2}\quad \begin{cases} A=20\\ a=6z-1\\ b=2z+3\\ h=z \end{cases}\implies 20=\cfrac{z[(6z-1)~+~(2z+3)]}{2} \\\\\\ 20=\cfrac{z(8z+2)}{2}\implies 20=\cfrac{2z(4z+1)}{2}\implies 20=z(4z+1) \\\\\\ 20=4z^2+z\implies 0=4z^2+z-20](https://tex.z-dn.net/?f=%5Cbf%20A%3D%5Ccfrac%7Bh%28a%2Bb%29%7D%7B2%7D%5Cquad%20%0A%5Cbegin%7Bcases%7D%0AA%3D20%5C%5C%0Aa%3D6z-1%5C%5C%0Ab%3D2z%2B3%5C%5C%0Ah%3Dz%0A%5Cend%7Bcases%7D%5Cimplies%2020%3D%5Ccfrac%7Bz%5B%286z-1%29~%2B~%282z%2B3%29%5D%7D%7B2%7D%0A%5C%5C%5C%5C%5C%5C%0A20%3D%5Ccfrac%7Bz%288z%2B2%29%7D%7B2%7D%5Cimplies%2020%3D%5Ccfrac%7B2z%284z%2B1%29%7D%7B2%7D%5Cimplies%2020%3Dz%284z%2B1%29%0A%5C%5C%5C%5C%5C%5C%0A20%3D4z%5E2%2Bz%5Cimplies%200%3D4z%5E2%2Bz-20)
since the height is just a length unit, it can't be -2.3646.
Its 20 such a silly question
The geometric mean would be 37.9
Move a2 to the left side of the equation so you have c2-a2. then divide by 2 to get b by itself. you are left with c2-a2 all over 2. the 2s will cancel and you'll be left with c-a=b
