Answer:
Since, an airplane descended 4,000 feet before landing.
Now, we have to determine the integer which represents the number of feet, the airplane was above the ground before its descent.
Before the descent, airplane was at the height of 4,000 feet.
And the distance above the ground is represented by the positive integers and distance below the ground is represented by the negative integers.
Since, 4,000 feet is the distance of airplane above the ground.
So, the airplane was +4,000 feet above the ground before its descent.
Answer:
f(4) = -8
General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Algebra I</u>
Step-by-step explanation:
<u>Step 1: Define</u>
f(x) = -x - 4
f(4) is x = 4
<u>Step 2: Evaluate</u>
- Substitute in <em>x</em>: f(4) = -4 - 4
- Subtract: f(4) = -8
Step-by-step explanation:
Triangles RQP and RBC are congruent.
Letters R and P are the 1st and 3rd letters in RQP.
Letters R and C are the 1st and 3rd letters in RBC.
Hence line RP = line RC = line CR (D).
Answer:
<u>135.73 ounces</u> of a silver alloy that costs $5.50 per ounce should be mixed.
Step-by-step explanation:
Given:
A silver alloy that costs $5.50 per ounce should be mixed with one that costs $7.00 per ounce to make a new 30 ounce alloy that costs $6.40 per ounce.
Now, to find the ounces of silver alloy.
Let the silver costs $5.50 per ounce be 
And the silver costs $7.00 per ounce be 
So, the total ounce make a new alloy:
....(1)
Now, the total costs of silver alloy:

Putting the value of
from equation (1) in the place of
:



<em>Subtracting both sides by 210 we get:</em>

<em>Dividing both sides by -1.5 we get:</em>

Therefore, 135.73 ounces of a silver alloy that costs $5.50 per ounce should be mixed.