First translate the English phrase "Four times the sum of a number and 15 is at least 120" into a mathematical inequality.
"Four times..." means we're multiplying something by 4.
"... the sum of a number and 15..." means we're adding an unknown and 15 and then multiplying the result by 4.
"... is at least 120" means when we substitute the unknown for a value, in order for that value to be in the solution set, it can only be less than or equal to 120.
So, the resulting inequality is 4(x + 15) ≤ 120.
Simplify the inequality.
4(x + 15) ≤ 120
4x + 60 ≤ 120 <-- Using the distributive property
4x ≤ 60 <-- Subtract both sides by 60
x ≤ 15 <-- Divide both sides by 4
Now that we have the inequality in a simplified form, we can easily see that in order to be in the solution set, the variable x can be no bigger than 15.
In interval notation it would look something like this:
[15, ∞)
In set builder notation it would look something like this:
{x | x ∈ R, x ≤ 15}
It is read as "the set of all x, such that x is a member of the real numbers and x is less than or equal to 15".
Answer: sec (75) or csc (15)
Step-by-step explanation:
255 is in the 3rd quadrant where the secant is. Here, the tangent and cotangent is positive.
Reference angle for 255 is,
255 - 180 = 75 degrees.
Therefore, sec (255) = sec (75)
= csc (90 - 75) = csc (15)
The slope is 2 i’m pretty sure
The true statement about the residual plot is (a) The regression line is a good model because there is no pattern in the residuals.
<h3>How to interpret the residual plot?</h3>
For a residual plot to be considered a good model, the points on the plot must be at random and they must not follow a specific pattern
From the graph, we can see that the points are scattered
Hence, the true statement about the residual plot is (a)
Read more about residual plots at:
brainly.com/question/9329287
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Answer:
2/11
Step-by-step explanation:
Probability is the LIKELIHOOD of an event.
According to the word problem, there are 11 people in total and 2 of them are being selected.
The probability of them being the 2 oldest people is 2 in 11, or 2/11.