1. If a - b = 4 and a + b = 12, what is the value of a?
2 answers:
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Answer: (x - 3)² + y² =
<u>Step-by-step explanation:</u>
Circle Formula: (x - h)² + (y - k)² = r² ; (h, k) is the center & r is the radius
Use the distance formula for (3, 0) and (1, )
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Center (h, k) = (3, 0) Radius (r) =
(x - h)² + (y - k)² = r²
(x - 3)² + (y - 0)² = ()²
(x - 3)² + y² =
Answer:
Step-by-step explanation:
Given that in an investigation of pregnancy-induced hypertension, one group of women with this disorder was treated with low-dose aspirin, and a second group was given a placebo. A sample consisting of 50 women who received aspirin has mean arterial blood pressure 120mmHg and standard deviation 10mmHg; a sample of 42 women who were given the placebo has mean blood pressure 115mmHg and standard deviation 12mmHg.
Population variances are equal
(two tailed test at 5% significance level)
Here x denotes group I and Y group II
N Mean StDev SE Mean
Sample 1 50 120 10 1.4142
Sample 2 42 115 12 1.8516
Pooled std deviation = 10.9565
df=80
Mean difference= 5
Test statistic t = mean diff/std error = =2.1803
p value = 0.0318
since p <0.05 we reject H0
b) We find p >0.01 hence at 1% significance level we accept H0
This implies that 99% confidence interval contains mean difference =0