Answer: (sec x – tan x)(csc x + 1).
Step-by-step explanation:
Answer:
The answers are in the attachment
Answer: That used to happen to me but if you answer peoples questions it doesnt do that anymore because you are helping out
Step-by-step explanation:
Answer:
-(20+z)/y = x
Step-by-step explanation:
-20=xy +z
Subtract z from each side
-20 -z = xy+z-z
-20 -z = xy
Divide each side by y
(-20 -z)/y = xy/y
Factor out a negative
-(20+z)/y = x
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
