Answer:

Step-by-step explanation:
Hello!
A trinomial is a expression consisting of three different terms
To turn this into a trinomial we multiply everything to each other
<u> 3x </u>
3x * x = 
3x * 10 = 30x
<u> 8 </u>
8 * x = 8x
8 * 10 = 80
Now we put them all together in an equation

Combine like terms

The answer is 
Hope this helps!
A suitable probability calculator can tell you the probability is about 6.7%.
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The standard deviation of the distribution of sample means is the population standard deviation (6) divided by the square root of the sample size (√144=12). Thus, your threshold is about (19.25-20)/(6/12) = -1.5 standard deviations from the mean.
The correct answer is D.
Sally is 3 years younger than Ralph therefore S=R-3 which means Sally is Ralph’s age minus 3.