Solve each problem. Volume of a Box A piece of sheet metal is 2.5 times as long as it is wide. It is to be made into a box with an open top by cutting 3 -inch squares from each corner and folding up the sides, as shown at the top of the next page. Let x
represent the width of the original piece of sheet metal. (a) Represent the length of the original piece of sheet metal in terms of x.
(b) What are the restrictions on x?
(c) Determine a function V
that represents the volume of the box in terms of x
(d) For what values of x
(that is, original widths) will the volume of the box be between 600 and 800 cubic inches? Determine the answer graphically, and give values to the nearest tenth of an inch
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
Parenthesis first
11+4=15
division second
15/3=5
what is the square root of 64? 8!
8x5=40
Answer is 40
To find the third side of a triangle (there are two answers you could get), you need to use the Pythagorean formula: a^2+b^2=c^2. First answer, 20^2+30^2=c^2. Solve for c. c=36.06. The second answer, 20^2+b^2=30^2. Solve for b. b=26.36.
Step-by-step explanation:
y = 8x² + 8x - 96
y = 8(x² + x - 12)
y = 8(x + 4)(x - 3)
When y = 0, 8(x + 4)(x - 3) = 0.
=> x = -4 or x = 3. (B)