The heights of dogs, in inches, in a city are normally distributed with a population standard deviation of 3 inches and an unknown population mean. if a random sample of 17 dogs is taken and results in a sample mean of 28 inches, find the error bound (ebm) of the confidence interval with a 90% confidence level.

1.2703

Step-by-step explanation:

Given : Sample size : n= 17, which is a small sample (n<30), so we use t-test.

Significance level :

Then , Critical value :

Standard deviation:

The formula to find the margin of error : -

Hence, the error bound (EBM) of the confidence interval with a 90% confidence level.=1.2703

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15