Answer:
11.4
20/100 = x/57
Step-by-step explanation:
It is perhaps simplest just to translate the given English sentence into a mathematical sentence.
... 20% ... ... of ... 57 ... is ... what number
... 20/100 ... × ... 57 .... = ... what number . . . . . . . . translation to math sentence
... 11.4 = what number . . . . . . . . carry out the multiplication
_____
If you're asked to write this as a proportion, you can write it like this:

You can solve this proportion by multiplying by 57 (the denominator under "what number"). Doing so gives you the same arithmetic sentence as shown above.
Answer:
The area of the triangle should be: [(1 + 5 + 4) × 11]/2= 55 (ft²)
The area of the rectangle should be: 5 × 2 = 10 (ft²)
The area of the shaded region is: 55 - 10 = 45 (ft²)
Answer:
x = -3/4
Step-by-step explanation:
<u>Step 1: Identify the equation</u>
8x + 3 = 4x
<u>Step 2: Move x's to one side and number to the other side</u>
8x + 3 - 4x - 3 = 4x - 4x - 3
4x = -3
<u>Step 3: Make x by itself</u>
4x / 4 = -3 / 4
x = -3/4
Answer: x = -3/4
3 times 7.75 = 23.25 + 7.75 = 31.00
so the basketball is $23.25 and the pump is $7.75
Answer:
The minimum unit cost is equal to $15,339
Step-by-step explanation:
Let
x ----> the number of engines
C ---> the cost in dollars to make each airplane engine
we have

This is a vertical parabola open upward (the leading coefficient is positive)
The vertex represent the minimum of the parabola
The minimum unit cost is equal to the y-coordinate of the vertex
Convert the quadratic equation into vertex form
Factor 0.5

Complete the square. Remember to balance the equation by adding the same constants to each side


Rewrite as perfect squares
----> equation into vertex form
The vertex is the point (100,15,339)
The y-coordinate of the vertex is 15,339
therefore
The minimum unit cost is equal to $15,339