Answer:
Step-by-step explanation:
Given that a solution containing 12% alcohol is to be mixed with a solution containing 4% alcohol to make 20 gallons of solution containing 9% alcohol.
Let x gallons of 12% alcohol be mixed with y gallons of 4% alcohol.
Total gallons
Alcohol content in the total mixture 

b) Two equations are

c) This is of the form Ax = B
where A =![\left[\begin{array}{ccc}1&1\\12&4\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%261%5C%5C12%264%5Cend%7Barray%7D%5Cright%5D)
Inverse is ![\frac{1}{4-12} \left[\begin{array}{ccc}4&-1\\-12&12\end{array}\right]\\=\frac{-1}{8} \left[\begin{array}{ccc}4&-1\\-12&12\end{array}\right]\\](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B4-12%7D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D4%26-1%5C%5C-12%2612%5Cend%7Barray%7D%5Cright%5D%5C%5C%3D%5Cfrac%7B-1%7D%7B8%7D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D4%26-1%5C%5C-12%2612%5Cend%7Barray%7D%5Cright%5D%5C%5C)
Solution set is A inverse *B
= 
In 18 minutes its 120 because you find the unit
Answer:
546 ft³
Step-by-step explanation:
In the figure attached, the top view of the pool is shown. It can be decomposed into a trapezoid which height is 12 ft and which bases are 9 ft and 11 ft; and a rectangle which height is 1.5 ft and and it base is 11 ft.
Area of the trapezoid: (9 + 11)/2 * 12 = 120 ft²
Area of the rectangle: 1.5*11 = 16.5 ft²
Total area: 120 + 16.5 = 136.5 ft²
Volume of the pool: Total area * deep = 136.5 * 4 = 546 ft³
Answer:
The answer is C
Step-by-step explanation:
Took the test!
Answer:
No
Step-by-step explanation:
y = 4x + 1 is not a direct variation. Direct variations have the form y = kx. So y = 4x would be a direct variation (k=4), but not y = 4x+1