Answer:
5, -9
Step-by-step explanation:
(x - 5)(x + 9) = 0 These are factors, to get the roots, just set each one equal to zero
x - 5 = 0
x = 5
x + 9 = 0
x = -9
Answer:
z≈3.16
p≈0.001
we reject the null hypothesis and conclude that the student knows more than half of the answers and is not just guessing in 0.05 significance level.
Step-by-step explanation:
As a result of step 2, we can assume normal distribution for the null hypothesis
<em>step 3:</em>
z statistic is computed as follows:
z=
where
- X is the proportion of correct answers in the test (
) - M is the expected proportion of correct answers according to the null hypothesis (0.5)
- p is the probability of correct answer (0.5)
- N is the total number of questions in the test (40)
z=
≈ 3.16
And corresponding p value for the z-statistic is p≈0.001.
Since p<0.05, we reject the null hypothesis and conclude that the student knows more than half of the answers and is not just guessing in 0.05 significance level.
The first thing you want to do is plug in x and y into both equations:
a(3) + b(4) = 4
b(3) + a(4) = 8
rearrange to line up a’s and b’s
3a + 4b = 4
4a + 3b = 8
now you want to choose a or b and multiply each equation by a number to make them have the same amount of a’s or b’s.
4(3a + 4b = 4) = 12a + 16b = 16
3(4a + 3b = 8) = 12a + 9b = 24
Now we subtract the bottom equation from the top and solve for b:
12a + 16b - (12a + 9b) = 16 - 24
7b = -8
b = -8/7
Now we plug back in for b to one of the original equations:
3a + 4(-8/7) = 4
3a + (-32/7) = 4
3a - (32/7) = 4
3a = 4 + (32/7)
3a = (28/7) + (32/7)
3a = 60/7
a = (60/7)/3 = 20/7.
Finally, plug a and b in together to double check using the second equation.
4a + 3b = 8
4(20/7) + 3(-8/7) = ?
(80/7) - (24/7) = ?
56/7 = 8.
Answer:
A
Step-by-step explanation:
-6(4 - x) <= -4(x + 1)
-24 + 6x <= -4x - 4
-24 + 10x <= -4
10x <= 20
x <= 2
