The sum of three and a number is 3+x
Answer:
15.95 feets
Step-by-step explanation:
Given that:
Angle of elevation = 62°
Using trigonometric relation :
Tanθ = opposite / Adjacent
From the drawing attached :
Opposite = 30 feets
Distance between girl and lighthouse = d
Tan 62 = 30 / d
1.8807264 * d = 30
d = 30 / 1.8807264
d = 15.951283
d = 15.95 feets
Answer:
B. 4.29
Step-by-step explanation:
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:
Step-by-step explanation:
Add 4 to both sides
13 + 4 = w/-3 - 4 + 4
17 = w/-3 Multiply through by -3
17*-3 = -3*(w/-3)
-51 = w