Answer:
This simple formula: area = 1/2 x perimeter x apothem.
It means: Perimeter × the sum of the lengths of all the sides.
Hope it helps!<3
Your correct b is the correct answer
-2+3x=2x+6+x
-2+3x= 3x+6
-3x = -3x
-2=6
No solution! -2 doesn’t not equal 6
Steps
1. Combine like terms( example combine like terms on the right side of the equation)
2. Subtract or add variable from one side
3. You get the answer
say we're going to add "x" gallons of water, now how many gallons of alcohol is in pure water? well 0%, and 0% of "x" is (0/100) * x = 0.
the 3 gallons we know are 100% alcohol, how many gallons of alcohol is in it? well (100/100) * 3 = 3.
the resulting mix will have x + 3 gallons total and it's going to be 15% alcohol, how many gallons of alcohol is that? (15/100) * (x+3).
now, the amount of alcohol never increased, so the original 3 gallons of only alcohol will remain even after the water has been added, so.
![\begin{array}{lcccl} &\stackrel{solution}{quantity}&\stackrel{\textit{\% of }}{amount}&\stackrel{\textit{gallons of }}{amount}\\ \cline{2-4}&\\ \textit{pure water}&x&0.00&0\\ \textit{pure alcohol}&3&1.00&3\\ \cline{2-4}&\\ mixture&x+3&0.15&0.15(x+3) \end{array} \begin{array}{llll} \\[3em] \leftarrow \textit{this amount}\\\\ \leftarrow \textit{must be equal to this one} \end{array} \\\\\\ 3 = 0.15(x+3)\implies 3=0.15x+0.45\implies 2.55=0.15x \\\\\\ \cfrac{2.55}{0.15}=x\implies 17=x](https://tex.z-dn.net/?f=%5Cbegin%7Barray%7D%7Blcccl%7D%20%26%5Cstackrel%7Bsolution%7D%7Bquantity%7D%26%5Cstackrel%7B%5Ctextit%7B%5C%25%20of%20%7D%7D%7Bamount%7D%26%5Cstackrel%7B%5Ctextit%7Bgallons%20of%20%7D%7D%7Bamount%7D%5C%5C%20%5Ccline%7B2-4%7D%26%5C%5C%20%5Ctextit%7Bpure%20water%7D%26x%260.00%260%5C%5C%20%5Ctextit%7Bpure%20alcohol%7D%263%261.00%263%5C%5C%20%5Ccline%7B2-4%7D%26%5C%5C%20mixture%26x%2B3%260.15%260.15%28x%2B3%29%20%5Cend%7Barray%7D%20%5Cbegin%7Barray%7D%7Bllll%7D%20%5C%5C%5B3em%5D%20%5Cleftarrow%20%5Ctextit%7Bthis%20amount%7D%5C%5C%5C%5C%20%5Cleftarrow%20%5Ctextit%7Bmust%20be%20equal%20to%20this%20one%7D%20%5Cend%7Barray%7D%20%5C%5C%5C%5C%5C%5C%203%20%3D%200.15%28x%2B3%29%5Cimplies%203%3D0.15x%2B0.45%5Cimplies%202.55%3D0.15x%20%5C%5C%5C%5C%5C%5C%20%5Ccfrac%7B2.55%7D%7B0.15%7D%3Dx%5Cimplies%2017%3Dx)