(3x - 1)(3 -x)+x^2 + 19
a)
(3x - 1)(3 -x)+x^2 + 19
=9x - 3x^2 - 3 + x + x^2 + 19
= -2x^2 + 10x + 16
b) evaluate at x = 2
-2x^2 + 10x + 16
= -2 (2^2) + 10(2) + 16
= -8 + 20 + 16
= 28
c)
from part (a)
-2x^2 + 10x + 16
= -2 (x^2 - 5x - 8) (complete factor)
Answer:
Step-by-step explanation:
Data given and notation
represent the sample mean given
represent the population standard deviation
sample size
represent the value that we want to test
t would represent the statistic (variable of interest)
State the null and alternative hypotheses.
We need to conduct a hypothesis in order to check if the true mean for the gasoline prices is lower than 1.25, the system of hypothesis would be:
Null hypothesis:
Alternative hypothesis:
If we analyze the size for the sample is > 30 but we don't know the population deviation so is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:
(1)
Calculate the statistic
We can replace in formula (1) the info given like this:
Answer:
1. {xx < 13} 3. {yy < 5} 5. {tt > -42} 7. {dd ≤ 4}
9. {kk ≥ -3} 11. {zz < -2} 13. {mm < 29}
15. {bb ≥ -16} 17. {zz > -2} 19. {bb ≤ 10}
21. {qq ≥ 2} 23. ⎧
⎨
⎩
ww ≥ - _7
3
⎫
⎬
⎭
Lesson 0-7
1. {(−15, 4), (−18, −8), (−16.5, −2),
Step-by-step explanation:
ZX + Zz = 180°, without the actual
measu