<span>(3a^2 - 2a + 4) - (a^2 - 3a + 7) = (distribute the negative sign)
3a^2 - 2a +4 - a^2 + 3a - 7 = (add like terms)
2a^2 + a - 3
So, the answer is A!
</span>
Answer:
23
Step-by-step explanation:
30 + 9 = 39.
39 - 14 = 25.
25 - 2
= 23
C) rhombus.
lines of symmetry can only go through symmetrical shapes. rhombuses are not symmetrical.
Answer:

Step-by-step explanation:
The confidence interval for the population mean x can be calculated as:

Where x' is the sample mean, s is the population standard deviation, n is the sample size and
is the z-score that let a proportion of
on the right tail.
is calculated as: 100%-99%=1%
So, 
Finally, replacing the values of x' by 308, s by 17, n by 15 and
by 2.576, we get that the confidence interval is:

Answer:
Yes
Step-by-step explanation:
Each value only maps out to one value, so that means it is a function.