Answer:
C
Step-by-step explanation:
Answer:
Option C i.e. 2 and 9, constants have a fixed value is a correct option.
Step-by-step explanation:
In algebra, a constant is basically a fixed value.
Sometimes, a constant is a number for a letter such as a, b, or c for a fixed number.
For example: in ''2x+7=3'', 7 and 3 are constants.
- <em>Please note that the number with variable x in the term is a coefficient.</em>
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In our case:
Given the equation

Therefore, 2 and 9 are constants, having a fixed value.
Thus, option C i.e. 2 and 9, constants have a fixed value is a correct option.
Answer:
see bottom
Step-by-step explanation:
divide through by 4
x2 - 2x - 3 = 0
x2 - 3x + x - 3 = 0
(x2 - 3x) + (x - 3) = 0
x(x - 3) + 1(x - 3) = 0
(x + 1) (x - 3) = 0
x + 1 = 0 and x - 3 = 0
x = -1 and x = 3
Given Information:
Mean weekly salary = μ = $490
Standard deviation of weekly salary = σ = $45
Required Information:
P(X > $525) = ?
Answer:
P(X > $525) = 21.77%
Step-by-step explanation:
We want to find out the probability that a randomly selected teacher earns more than $525 a week.

The z-score corresponding to 0.78 from the z-table is 0.7823

Therefore, there is 21.77% probability that a randomly selected teacher earns more than $525 a week.
How to use z-table?
Step 1:
In the z-table, find the two-digit number on the left side corresponding to your z-score. (e.g 0.7, 2.2, 1.5 etc.)
Step 2:
Then look up at the top of z-table to find the remaining decimal point in the range of 0.00 to 0.09. (e.g. if you are looking for 0.78 then go for 0.08 column)
Step 3:
Finally, find the corresponding probability from the z-table at the intersection of step 1 and step 2.
Answer:
4.5587
Step-by-step explanation:
this is because standard form of numbers are supposed to be 1 and 9