(3a-7)^2
1. 9a^2-21a-21a+49
2. 3a(3a-7)-7(3a-7)
3. (3a-7)(3a-7)
4. Combine like terms
Solution: We are given:
μ=3.1,σ=0.5,n=50
We have to find P(Mean <2.9)
We need to first find the z score
z= (xbar-μ)/(σ/sqrt(n))
=(2.9-3.1)/(0.5/sqrt(50))
=(-0.2)/0.0707
=-2.83
Now we have to find P(z<-2.83)
Using the standard normal table, we have:
P(z<-2.83)=0.0023
Therefore the probability of the sample mean being less the 2.9 inches is 0.0023
Answer:
3x + 12
Step-by-step explanation:
I got this answer because since 8x and -5x are like terms, you are able to subtract them from each other. 8x-5x is 3x. Since you cant add 12 to 5x because they aren't like terms, you leave the expression as it is right now. Finally, your answer is 3x + 12.
Hope I helped! Have a good day.