Answer:
therefore f(x)=100x-5-1 has an x-intercept
Answer:
The null and alternative hypotheses are:
Under the null hypothesis, the test statistic is:
Where:
is the sample mean
is the sample standard deviation
is the sample size
Now, the right tailed t critical value at 0.05 significance level for df = n-1 = 10-1 = 9 is:
Since the t statistic is less than the t critical value at 0.05 significance level, therefore,we fail to reject the null hypothesis and conclude that there is not sufficient evidence to support the claim that the average phone bill has increased.
Since angle C is not 90 degrees, it's one of the acute angles
in the right triangle.
(The side adjacent to angle C ) divided by (hypotenuse)
is the cosine of angle C .
(adjacent) / (10 inches) = cos(40 degrees)
Multiply each side by (10 inches):
Adjacent side = (10 inches) x cos(40) =
(10 inches) x 0.766 =
7.66 inches (rounded)
Answer:
W ≈ 5.2 cm
Step-by-step explanation:
Represent the length and width by L and W respectively.
Then L * W = 81 cm^2, and L = 3W.
Substituting 3W for L in the first equation, we get:
3W * W - 81 = 0, or 3W^2 - 81 = 0.
To make it easier to find the final answer, rewrite 3W^2 - 81 = 0 as
81
W^2 = ------- = 27
3
Then W (the width) is the positive square root of 27, or W ≈ 5.2 cm
