You would distribute the 2x to the x and 1= 2x^2+2x
then you would distribute the 1 to the x and 1= 1x+1
then you would add it all together to get
2x^2+3x+1
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:
95% of the population spent between 16.8 hours to 26.2 hours on social media per month
Step-by-step explanation:
- subtracting 1 from sample size: 83-1= 82
- Note Mean=21.5 and standard deviation=2.5
- Subtracting confidence interval from 1 and dividing by 2: (1-0.95)/2=0.025
- At α=0.025 and dF=82, the t-distribution table gives 1.984
- Divide standard deviation by square root of sample size: 21.5/√83= 2.36
- Multiplying answer in step 4 by answer in step 5: 2.36×1.984= 4.68
- For lower end: 21.5-4.68= 16.82
- for upper end: 21.5+4.68=26.18
Answer:
2 over 5
Step-by-step explanation:
Common ratio =
7/ (35/2) = (14/2) / 7
Our answer became 2/5
Answer:
ΔABX and ΔEDX
Step-by-step explanation:
Given: AX ≅ EX
BX ≅ DX
SAS implies a congruent relation with respect to Side-Angle-Side between the two required triangle.
AX ≅ EX (given)
BX ≅ DX (given)
<BXA ≅ <DXE (vertical opposite angles)
Therefore,
ΔABX ≅ ΔEDX (Side-Angle-Side, SAS, congruence property)