Definition
Variable
-> a quantity whose value may change during a given discussion or problem.
-> It is denoted usually by the last alphabetical letter such as x, y and z.
Constants
-> a quantity whose value is fixed during a given discussion or problem.
-> It is denoted fixed values such as 3, 5 , 7, etc.
Absolute Value
-> It is indicated by inclosing the constant by two vertical parallel lines.
-> It is denoted by | |.
Range of a variable
-> those are the values that may be given to the variable and will depend on the particular problem or discussion.
Example |
1. Find the answer from this given:
| -3 |
Steps:
a. Inverse the input.
b. Compute.
= | -3 |
= 3
Exercises |
Steps:
a. Inverse the input.
b. Compute.
Solution:
= |-7|
= 7
Answer: 7
2. Find the answer from this given: |x - 3| = 5.
Steps:
a. Inverse the input.
b. Interchange.
c. Compute.
Solution:
= |x - 3| = 5
= x - 3 = 5; x = 5 + 3
= 8
Answer: 8
3. Find the answer from this given: 2x + 5, if x = 3.
Steps:
a. Substitute the x.
b. Compute.
Solution:
= 2x + 5
= 2(3) + 5
= 11
Answer: 11
4. Find the answer from this given: y = 3x + 2, if x is equal to 1 & 4.
Steps:
a. Substitute the x.
b. Compute.
Solution:
= y = 3x + 2; if x = 1
= y = 3(1) + 2
= 5
= y = 3x + 2; if x = 4
= y = 3(4) + 2
= 14
= y [5,14]
Answer: y [5,14]
5. Find the answer from this given: x2 + C, if C = 7 & x = 2.
Steps:
a. Substitute the x and C.
b. Compute.
Solution:
= x2 + C
= (4) + 7
= 11
Answer: 11