Answer: choice A. 40 liters
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Explanation:
x = number of liters of the 50% alcohol solution
If we have x liters of 50% alcohol, then we have 0.50*x liters of pure alcohol. This is added to 0.90*40 = 36 liters of pure alcohol (from the 90% solution).
So far we have 0.50*x + 36. This expression represents the total amount of pure alcohol. We want a 70% solution, so we want 70% of the total 40+x meaning 0.50*x + 36 is to be set equal to 0.70*(40+x) and we solve for x as shown below
0.50*x + 36 = 0.70*(40+x)
0.50*x + 36 = 0.70*(40)+0.70*(x)
0.50*x + 36 = 28+0.70*x
36 - 28 = 0.70*x - 0.50x
8 = 0.20x
0.20x = 8
x = 8/0.20
x = 40
So that is why the answer is choice A. 40 liters
Answer: -2
I'm not so sure what it means by slope, but because I saw a pattern between x and y (it decreases by 2 every x value and decreases by 4 every TWO x values) values so I would pick -2. BUT I don't know if the answer is -4.
Step-by-step explanation:
Answer:
B and E
Step-by-step explanation:
A. -7 ÷ (-4) = -7/-4 = 7/4 = 1.75
B. -(3 ÷ 2) = -(1.5) = -1.5
C. -8/5 * (-5/8) = (8/5) * (5/8) = 1
D. -5/-3 = 5/3 ≈ 1.667
E. -9 ÷ 6 = -9/6 = -1.5
Expanded form is writing out everything and no simplifying.
A. c times c
B. t times t times t times t
C. 2 times x times x times x
D. 4 times 4 times h times h
E. 2 times 2 times 2 times l times l times l
F. a times a times a + 7 times b times b
Hope this helps :)
