Answer:
a = 20
Step-by-step explanation:
7a + 2a + a − 9a = 20
Combine like terms
10a -9a = 20
a =20
<span>{2 x×0 + 10 x = 3 u(t - 12) - (5 δ(t - 4)) x(0) = -1, x×0×0 = -2}
</span><span>{10 x = 3 u(t - 12) - 5 x(0) δ(t - 4) = -1, False}</span>
Answer:
Ben needs to get a 99% on his second test
Step-by-step explanation:
The average is the sum of both test scores, divided by the total number of test scores (2).
Let x by the grade Ben must receive on his second test.
(89 + x)/2 = 94
Multiply by 2 on both sides
89 + x = 188
Subtract 89 on both sides
x = 99
Check work:
(89 + 99)/2 = 188/2 = 99
Answer:
Positive
Step-by-step explanation:
Since there are two x-intercepts, -2 and 2, there is a positive discriminant. If the parabola was below the x axis and opened downwards, the discriminant would be negative.
The hypothesis test shows that we reject the null hypothesis and there is sufficient evidence to support the claim that the return rate is less than 20%
<h3>What is the claim that the return rate is less than 20% by using a statistical hypothesis method?</h3>
The claim that the return rate is less than 20% is p < 0.2. From the given information, we can compute our null hypothesis and alternative hypothesis as:


Given that:
Sample size (n) = 6965
Sample proportion 
The test statistics for this data can be computed as:



z = -2.73
From the hypothesis testing, since the p < alternative hypothesis, then our test is a left-tailed test(one-tailed.
Hence, the p-value for the test statistics can be computed as:
P-value = P(Z ≤ z)
P-value = P(Z ≤ - 2.73)
By using the Excel function =NORMDIST (-2.73)
P-value = 0.00317
P-value ≅ 0.003
Therefore, we can conclude that since P-value is less than the significance level at ∝ = 0.01, we reject the null hypothesis and there is sufficient evidence to support the claim that the return rate is less than 20%
Learn more about hypothesis testing here:
brainly.com/question/15980493
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